1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2004, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 2, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING. If not, write --
19 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
20 -- MA 02111-1307, USA. --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
25 ------------------------------------------------------------------------------
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Debug; use Debug;
30 with Einfo; use Einfo;
31 with Elists; use Elists;
32 with Errout; use Errout;
33 with Expander; use Expander;
34 with Exp_Ch7; use Exp_Ch7;
35 with Fname; use Fname;
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_Ch10; use Sem_Ch10;
52 with Sem_Ch12; use Sem_Ch12;
53 with Sem_Disp; use Sem_Disp;
54 with Sem_Dist; use Sem_Dist;
55 with Sem_Elim; use Sem_Elim;
56 with Sem_Eval; use Sem_Eval;
57 with Sem_Mech; use Sem_Mech;
58 with Sem_Prag; use Sem_Prag;
59 with Sem_Res; use Sem_Res;
60 with Sem_Util; use Sem_Util;
61 with Sem_Type; use Sem_Type;
62 with Sem_Warn; use Sem_Warn;
63 with Sinput; use Sinput;
64 with Stand; use Stand;
65 with Sinfo; use Sinfo;
66 with Sinfo.CN; use Sinfo.CN;
67 with Snames; use Snames;
68 with Stringt; use Stringt;
70 with Stylesw; use Stylesw;
71 with Tbuild; use Tbuild;
72 with Uintp; use Uintp;
73 with Urealp; use Urealp;
74 with Validsw; use Validsw;
76 package body Sem_Ch6 is
78 -----------------------
79 -- Local Subprograms --
80 -----------------------
82 procedure Analyze_Generic_Subprogram_Body (N : Node_Id; Gen_Id : Entity_Id);
83 -- Analyze a generic subprogram body. N is the body to be analyzed,
84 -- and Gen_Id is the defining entity Id for the corresponding spec.
86 procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id);
87 -- If a subprogram has pragma Inline and inlining is active, use generic
88 -- machinery to build an unexpanded body for the subprogram. This body is
89 -- subsequenty used for inline expansions at call sites. If subprogram can
90 -- be inlined (depending on size and nature of local declarations) this
91 -- function returns true. Otherwise subprogram body is treated normally.
92 -- If proper warnings are enabled and the subprogram contains a construct
93 -- that cannot be inlined, the offending construct is flagged accordingly.
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_Overriding_Operation
123 -- Check that a subprogram with a pragma Overriding or Optional_Overriding
124 -- is legal. This check is performed here rather than in Sem_Prag because
125 -- the pragma must follow immediately the declaration, and can be treated
126 -- as part of the declaration itself, as described in AI-218.
128 procedure Check_Subprogram_Order (N : Node_Id);
129 -- N is the N_Subprogram_Body node for a subprogram. This routine applies
130 -- the alpha ordering rule for N if this ordering requirement applicable.
132 function Is_Non_Overriding_Operation
134 New_E : Entity_Id) return Boolean;
135 -- Enforce the rule given in 12.3(18): a private operation in an instance
136 -- overrides an inherited operation only if the corresponding operation
137 -- was overriding in the generic. This can happen for primitive operations
138 -- of types derived (in the generic unit) from formal private or formal
141 procedure Check_Returns
145 -- Called to check for missing return statements in a function body,
146 -- or for returns present in a procedure body which has No_Return set.
147 -- L is the handled statement sequence for the subprogram body. This
148 -- procedure checks all flow paths to make sure they either have a
149 -- return (Mode = 'F') or do not have a return (Mode = 'P'). The flag
150 -- Err is set if there are any control paths not explicitly terminated
151 -- by a return in the function case, and is True otherwise.
153 function Conforming_Types
156 Ctype : Conformance_Type;
157 Get_Inst : Boolean := False) return Boolean;
158 -- Check that two formal parameter types conform, checking both
159 -- for equality of base types, and where required statically
160 -- matching subtypes, depending on the setting of Ctype.
162 procedure Enter_Overloaded_Entity (S : Entity_Id);
163 -- This procedure makes S, a new overloaded entity, into the first
164 -- visible entity with that name.
166 procedure Install_Entity (E : Entity_Id);
167 -- Make single entity visible. Used for generic formals as well.
169 procedure Install_Formals (Id : Entity_Id);
170 -- On entry to a subprogram body, make the formals visible. Note
171 -- that simply placing the subprogram on the scope stack is not
172 -- sufficient: the formals must become the current entities for
175 procedure Make_Inequality_Operator (S : Entity_Id);
176 -- Create the declaration for an inequality operator that is implicitly
177 -- created by a user-defined equality operator that yields a boolean.
179 procedure May_Need_Actuals (Fun : Entity_Id);
180 -- Flag functions that can be called without parameters, i.e. those that
181 -- have no parameters, or those for which defaults exist for all parameters
183 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id);
184 -- If there is a separate spec for a subprogram or generic subprogram,
185 -- the formals of the body are treated as references to the corresponding
186 -- formals of the spec. This reference does not count as an actual use of
187 -- the formal, in order to diagnose formals that are unused in the body.
189 procedure Set_Formal_Validity (Formal_Id : Entity_Id);
190 -- Formal_Id is an formal parameter entity. This procedure deals with
191 -- setting the proper validity status for this entity, which depends
192 -- on the kind of parameter and the validity checking mode.
194 ---------------------------------------------
195 -- Analyze_Abstract_Subprogram_Declaration --
196 ---------------------------------------------
198 procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is
199 Designator : constant Entity_Id :=
200 Analyze_Subprogram_Specification (Specification (N));
201 Scop : constant Entity_Id := Current_Scope;
204 Generate_Definition (Designator);
205 Set_Is_Abstract (Designator);
206 New_Overloaded_Entity (Designator);
207 Check_Delayed_Subprogram (Designator);
209 Set_Categorization_From_Scope (Designator, Scop);
211 if Ekind (Scope (Designator)) = E_Protected_Type then
213 ("abstract subprogram not allowed in protected type", N);
216 Generate_Reference_To_Formals (Designator);
217 end Analyze_Abstract_Subprogram_Declaration;
219 ----------------------------
220 -- Analyze_Function_Call --
221 ----------------------------
223 procedure Analyze_Function_Call (N : Node_Id) is
224 P : constant Node_Id := Name (N);
225 L : constant List_Id := Parameter_Associations (N);
231 -- If error analyzing name, then set Any_Type as result type and return
233 if Etype (P) = Any_Type then
234 Set_Etype (N, Any_Type);
238 -- Otherwise analyze the parameters
243 while Present (Actual) loop
245 Check_Parameterless_Call (Actual);
251 end Analyze_Function_Call;
253 -------------------------------------
254 -- Analyze_Generic_Subprogram_Body --
255 -------------------------------------
257 procedure Analyze_Generic_Subprogram_Body
261 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
262 Kind : constant Entity_Kind := Ekind (Gen_Id);
268 -- Copy body and disable expansion while analyzing the generic
269 -- For a stub, do not copy the stub (which would load the proper body),
270 -- this will be done when the proper body is analyzed.
272 if Nkind (N) /= N_Subprogram_Body_Stub then
273 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
278 Spec := Specification (N);
280 -- Within the body of the generic, the subprogram is callable, and
281 -- behaves like the corresponding non-generic unit.
283 Body_Id := Defining_Entity (Spec);
285 if Kind = E_Generic_Procedure
286 and then Nkind (Spec) /= N_Procedure_Specification
288 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
291 elsif Kind = E_Generic_Function
292 and then Nkind (Spec) /= N_Function_Specification
294 Error_Msg_N ("invalid body for generic function ", Body_Id);
298 Set_Corresponding_Body (Gen_Decl, Body_Id);
300 if Has_Completion (Gen_Id)
301 and then Nkind (Parent (N)) /= N_Subunit
303 Error_Msg_N ("duplicate generic body", N);
306 Set_Has_Completion (Gen_Id);
309 if Nkind (N) = N_Subprogram_Body_Stub then
310 Set_Ekind (Defining_Entity (Specification (N)), Kind);
312 Set_Corresponding_Spec (N, Gen_Id);
315 if Nkind (Parent (N)) = N_Compilation_Unit then
316 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
319 -- Make generic parameters immediately visible in the body. They are
320 -- needed to process the formals declarations. Then make the formals
321 -- visible in a separate step.
327 First_Ent : Entity_Id;
330 First_Ent := First_Entity (Gen_Id);
333 while Present (E) and then not Is_Formal (E) loop
338 Set_Use (Generic_Formal_Declarations (Gen_Decl));
340 -- Now generic formals are visible, and the specification can be
341 -- analyzed, for subsequent conformance check.
343 Body_Id := Analyze_Subprogram_Specification (Spec);
345 -- Make formal parameters visible
349 -- E is the first formal parameter, we loop through the formals
350 -- installing them so that they will be visible.
352 Set_First_Entity (Gen_Id, E);
353 while Present (E) loop
359 -- Visible generic entity is callable within its own body.
361 Set_Ekind (Gen_Id, Ekind (Body_Id));
362 Set_Ekind (Body_Id, E_Subprogram_Body);
363 Set_Convention (Body_Id, Convention (Gen_Id));
364 Set_Scope (Body_Id, Scope (Gen_Id));
365 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
367 if Nkind (N) = N_Subprogram_Body_Stub then
369 -- No body to analyze, so restore state of generic unit.
371 Set_Ekind (Gen_Id, Kind);
372 Set_Ekind (Body_Id, Kind);
374 if Present (First_Ent) then
375 Set_First_Entity (Gen_Id, First_Ent);
382 -- If this is a compilation unit, it must be made visible
383 -- explicitly, because the compilation of the declaration,
384 -- unlike other library unit declarations, does not. If it
385 -- is not a unit, the following is redundant but harmless.
387 Set_Is_Immediately_Visible (Gen_Id);
388 Reference_Body_Formals (Gen_Id, Body_Id);
390 Set_Actual_Subtypes (N, Current_Scope);
391 Analyze_Declarations (Declarations (N));
393 Analyze (Handled_Statement_Sequence (N));
395 Save_Global_References (Original_Node (N));
397 -- Prior to exiting the scope, include generic formals again
398 -- (if any are present) in the set of local entities.
400 if Present (First_Ent) then
401 Set_First_Entity (Gen_Id, First_Ent);
404 Check_References (Gen_Id);
407 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
409 Check_Subprogram_Order (N);
411 -- Outside of its body, unit is generic again.
413 Set_Ekind (Gen_Id, Kind);
414 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
415 Style.Check_Identifier (Body_Id, Gen_Id);
417 end Analyze_Generic_Subprogram_Body;
419 -----------------------------
420 -- Analyze_Operator_Symbol --
421 -----------------------------
423 -- An operator symbol such as "+" or "and" may appear in context where
424 -- the literal denotes an entity name, such as "+"(x, y) or in a
425 -- context when it is just a string, as in (conjunction = "or"). In
426 -- these cases the parser generates this node, and the semantics does
427 -- the disambiguation. Other such case are actuals in an instantiation,
428 -- the generic unit in an instantiation, and pragma arguments.
430 procedure Analyze_Operator_Symbol (N : Node_Id) is
431 Par : constant Node_Id := Parent (N);
434 if (Nkind (Par) = N_Function_Call and then N = Name (Par))
435 or else Nkind (Par) = N_Function_Instantiation
436 or else (Nkind (Par) = N_Indexed_Component and then N = Prefix (Par))
437 or else (Nkind (Par) = N_Pragma_Argument_Association
438 and then not Is_Pragma_String_Literal (Par))
439 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
440 or else (Nkind (Par) = N_Attribute_Reference
441 and then Attribute_Name (Par) /= Name_Value)
443 Find_Direct_Name (N);
446 Change_Operator_Symbol_To_String_Literal (N);
449 end Analyze_Operator_Symbol;
451 -----------------------------------
452 -- Analyze_Parameter_Association --
453 -----------------------------------
455 procedure Analyze_Parameter_Association (N : Node_Id) is
457 Analyze (Explicit_Actual_Parameter (N));
458 end Analyze_Parameter_Association;
460 ----------------------------
461 -- Analyze_Procedure_Call --
462 ----------------------------
464 procedure Analyze_Procedure_Call (N : Node_Id) is
465 Loc : constant Source_Ptr := Sloc (N);
466 P : constant Node_Id := Name (N);
467 Actuals : constant List_Id := Parameter_Associations (N);
471 procedure Analyze_Call_And_Resolve;
472 -- Do Analyze and Resolve calls for procedure call
474 ------------------------------
475 -- Analyze_Call_And_Resolve --
476 ------------------------------
478 procedure Analyze_Call_And_Resolve is
480 if Nkind (N) = N_Procedure_Call_Statement then
482 Resolve (N, Standard_Void_Type);
486 end Analyze_Call_And_Resolve;
488 -- Start of processing for Analyze_Procedure_Call
491 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
492 -- a procedure call or an entry call. The prefix may denote an access
493 -- to subprogram type, in which case an implicit dereference applies.
494 -- If the prefix is an indexed component (without implicit defererence)
495 -- then the construct denotes a call to a member of an entire family.
496 -- If the prefix is a simple name, it may still denote a call to a
497 -- parameterless member of an entry family. Resolution of these various
498 -- interpretations is delicate.
502 -- If error analyzing prefix, then set Any_Type as result and return
504 if Etype (P) = Any_Type then
505 Set_Etype (N, Any_Type);
509 -- Otherwise analyze the parameters
511 if Present (Actuals) then
512 Actual := First (Actuals);
514 while Present (Actual) loop
516 Check_Parameterless_Call (Actual);
521 -- Special processing for Elab_Spec and Elab_Body calls
523 if Nkind (P) = N_Attribute_Reference
524 and then (Attribute_Name (P) = Name_Elab_Spec
525 or else Attribute_Name (P) = Name_Elab_Body)
527 if Present (Actuals) then
529 ("no parameters allowed for this call", First (Actuals));
533 Set_Etype (N, Standard_Void_Type);
536 elsif Is_Entity_Name (P)
537 and then Is_Record_Type (Etype (Entity (P)))
538 and then Remote_AST_I_Dereference (P)
542 elsif Is_Entity_Name (P)
543 and then Ekind (Entity (P)) /= E_Entry_Family
545 if Is_Access_Type (Etype (P))
546 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
547 and then No (Actuals)
548 and then Comes_From_Source (N)
550 Error_Msg_N ("missing explicit dereference in call", N);
553 Analyze_Call_And_Resolve;
555 -- If the prefix is the simple name of an entry family, this is
556 -- a parameterless call from within the task body itself.
558 elsif Is_Entity_Name (P)
559 and then Nkind (P) = N_Identifier
560 and then Ekind (Entity (P)) = E_Entry_Family
561 and then Present (Actuals)
562 and then No (Next (First (Actuals)))
564 -- Can be call to parameterless entry family. What appears to be
565 -- the sole argument is in fact the entry index. Rewrite prefix
566 -- of node accordingly. Source representation is unchanged by this
570 Make_Indexed_Component (Loc,
572 Make_Selected_Component (Loc,
573 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
574 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
575 Expressions => Actuals);
577 Set_Etype (New_N, Standard_Void_Type);
578 Set_Parameter_Associations (N, No_List);
579 Analyze_Call_And_Resolve;
581 elsif Nkind (P) = N_Explicit_Dereference then
582 if Ekind (Etype (P)) = E_Subprogram_Type then
583 Analyze_Call_And_Resolve;
585 Error_Msg_N ("expect access to procedure in call", P);
588 -- The name can be a selected component or an indexed component
589 -- that yields an access to subprogram. Such a prefix is legal if
590 -- the call has parameter associations.
592 elsif Is_Access_Type (Etype (P))
593 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
595 if Present (Actuals) then
596 Analyze_Call_And_Resolve;
598 Error_Msg_N ("missing explicit dereference in call ", N);
601 -- If not an access to subprogram, then the prefix must resolve to
602 -- the name of an entry, entry family, or protected operation.
604 -- For the case of a simple entry call, P is a selected component
605 -- where the prefix is the task and the selector name is the entry.
606 -- A call to a protected procedure will have the same syntax. If
607 -- the protected object contains overloaded operations, the entity
608 -- may appear as a function, the context will select the operation
609 -- whose type is Void.
611 elsif Nkind (P) = N_Selected_Component
612 and then (Ekind (Entity (Selector_Name (P))) = E_Entry
614 Ekind (Entity (Selector_Name (P))) = E_Procedure
616 Ekind (Entity (Selector_Name (P))) = E_Function)
618 Analyze_Call_And_Resolve;
620 elsif Nkind (P) = N_Selected_Component
621 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
622 and then Present (Actuals)
623 and then No (Next (First (Actuals)))
625 -- Can be call to parameterless entry family. What appears to be
626 -- the sole argument is in fact the entry index. Rewrite prefix
627 -- of node accordingly. Source representation is unchanged by this
631 Make_Indexed_Component (Loc,
632 Prefix => New_Copy (P),
633 Expressions => Actuals);
635 Set_Etype (New_N, Standard_Void_Type);
636 Set_Parameter_Associations (N, No_List);
637 Analyze_Call_And_Resolve;
639 -- For the case of a reference to an element of an entry family, P is
640 -- an indexed component whose prefix is a selected component (task and
641 -- entry family), and whose index is the entry family index.
643 elsif Nkind (P) = N_Indexed_Component
644 and then Nkind (Prefix (P)) = N_Selected_Component
645 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
647 Analyze_Call_And_Resolve;
649 -- If the prefix is the name of an entry family, it is a call from
650 -- within the task body itself.
652 elsif Nkind (P) = N_Indexed_Component
653 and then Nkind (Prefix (P)) = N_Identifier
654 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
657 Make_Selected_Component (Loc,
658 Prefix => New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
659 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
660 Rewrite (Prefix (P), New_N);
662 Analyze_Call_And_Resolve;
664 -- Anything else is an error.
667 Error_Msg_N ("Invalid procedure or entry call", N);
669 end Analyze_Procedure_Call;
671 ------------------------------
672 -- Analyze_Return_Statement --
673 ------------------------------
675 procedure Analyze_Return_Statement (N : Node_Id) is
676 Loc : constant Source_Ptr := Sloc (N);
678 Scope_Id : Entity_Id;
683 -- Find subprogram or accept statement enclosing the return statement
686 for J in reverse 0 .. Scope_Stack.Last loop
687 Scope_Id := Scope_Stack.Table (J).Entity;
688 exit when Ekind (Scope_Id) /= E_Block and then
689 Ekind (Scope_Id) /= E_Loop;
692 pragma Assert (Present (Scope_Id));
694 Kind := Ekind (Scope_Id);
695 Expr := Expression (N);
697 if Kind /= E_Function
698 and then Kind /= E_Generic_Function
699 and then Kind /= E_Procedure
700 and then Kind /= E_Generic_Procedure
701 and then Kind /= E_Entry
702 and then Kind /= E_Entry_Family
704 Error_Msg_N ("illegal context for return statement", N);
706 elsif Present (Expr) then
707 if Kind = E_Function or else Kind = E_Generic_Function then
708 Set_Return_Present (Scope_Id);
709 R_Type := Etype (Scope_Id);
710 Set_Return_Type (N, R_Type);
711 Analyze_And_Resolve (Expr, R_Type);
713 if (Is_Class_Wide_Type (Etype (Expr))
714 or else Is_Dynamically_Tagged (Expr))
715 and then not Is_Class_Wide_Type (R_Type)
718 ("dynamically tagged expression not allowed!", Expr);
721 Apply_Constraint_Check (Expr, R_Type);
723 -- ??? A real run-time accessibility check is needed
724 -- in cases involving dereferences of access parameters.
725 -- For now we just check the static cases.
727 if Is_Return_By_Reference_Type (Etype (Scope_Id))
728 and then Object_Access_Level (Expr)
729 > Subprogram_Access_Level (Scope_Id)
732 Make_Raise_Program_Error (Loc,
733 Reason => PE_Accessibility_Check_Failed));
737 ("cannot return a local value by reference?", N);
739 ("& will be raised at run time?!",
740 N, Standard_Program_Error);
743 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
744 Error_Msg_N ("procedure cannot return value (use function)", N);
747 Error_Msg_N ("accept statement cannot return value", N);
750 -- No expression present
753 if Kind = E_Function or Kind = E_Generic_Function then
754 Error_Msg_N ("missing expression in return from function", N);
757 if (Ekind (Scope_Id) = E_Procedure
758 or else Ekind (Scope_Id) = E_Generic_Procedure)
759 and then No_Return (Scope_Id)
762 ("RETURN statement not allowed (No_Return)", N);
766 Check_Unreachable_Code (N);
767 end Analyze_Return_Statement;
769 -----------------------------
770 -- Analyze_Subprogram_Body --
771 -----------------------------
773 -- This procedure is called for regular subprogram bodies, generic bodies,
774 -- and for subprogram stubs of both kinds. In the case of stubs, only the
775 -- specification matters, and is used to create a proper declaration for
776 -- the subprogram, or to perform conformance checks.
778 procedure Analyze_Subprogram_Body (N : Node_Id) is
779 Loc : constant Source_Ptr := Sloc (N);
780 Body_Spec : constant Node_Id := Specification (N);
781 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
782 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
783 Body_Deleted : constant Boolean := False;
787 Spec_Decl : Node_Id := Empty;
788 Last_Formal : Entity_Id := Empty;
789 Conformant : Boolean;
790 Missing_Ret : Boolean;
793 procedure Check_Following_Pragma;
794 -- If front-end inlining is enabled, look ahead to recognize a pragma
795 -- that may appear after the body.
797 procedure Check_Following_Pragma is
800 if Front_End_Inlining
801 and then Is_List_Member (N)
802 and then Present (Spec_Decl)
803 and then List_Containing (N) = List_Containing (Spec_Decl)
808 and then Nkind (Prag) = N_Pragma
809 and then Get_Pragma_Id (Chars (Prag)) = Pragma_Inline
812 (Expression (First (Pragma_Argument_Associations (Prag))))
818 end Check_Following_Pragma;
822 Write_Str ("==== Compiling subprogram body ");
823 Write_Name (Chars (Body_Id));
824 Write_Str (" from ");
825 Write_Location (Loc);
829 Trace_Scope (N, Body_Id, " Analyze subprogram");
831 -- Generic subprograms are handled separately. They always have
832 -- a generic specification. Determine whether current scope has
833 -- a previous declaration.
835 -- If the subprogram body is defined within an instance of the
836 -- same name, the instance appears as a package renaming, and
837 -- will be hidden within the subprogram.
840 and then not Is_Overloadable (Prev_Id)
841 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
842 or else Comes_From_Source (Prev_Id))
844 if Is_Generic_Subprogram (Prev_Id) then
846 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
847 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
849 Analyze_Generic_Subprogram_Body (N, Spec_Id);
853 -- Previous entity conflicts with subprogram name.
854 -- Attempting to enter name will post error.
856 Enter_Name (Body_Id);
860 -- Non-generic case, find the subprogram declaration, if one was
861 -- seen, or enter new overloaded entity in the current scope.
862 -- If the current_entity is the body_id itself, the unit is being
863 -- analyzed as part of the context of one of its subunits. No need
864 -- to redo the analysis.
866 elsif Prev_Id = Body_Id
867 and then Has_Completion (Body_Id)
872 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
874 if Nkind (N) = N_Subprogram_Body_Stub
875 or else No (Corresponding_Spec (N))
877 Spec_Id := Find_Corresponding_Spec (N);
879 -- If this is a duplicate body, no point in analyzing it
881 if Error_Posted (N) then
885 -- A subprogram body should cause freezing of its own
886 -- declaration, but if there was no previous explicit
887 -- declaration, then the subprogram will get frozen too
888 -- late (there may be code within the body that depends
889 -- on the subprogram having been frozen, such as uses of
890 -- extra formals), so we force it to be frozen here.
891 -- Same holds if the body and the spec are compilation units.
894 Freeze_Before (N, Body_Id);
896 elsif Nkind (Parent (N)) = N_Compilation_Unit then
897 Freeze_Before (N, Spec_Id);
900 Spec_Id := Corresponding_Spec (N);
904 -- Do not inline any subprogram that contains nested subprograms,
905 -- since the backend inlining circuit seems to generate uninitialized
906 -- references in this case. We know this happens in the case of front
907 -- end ZCX support, but it also appears it can happen in other cases
908 -- as well. The backend often rejects attempts to inline in the case
909 -- of nested procedures anyway, so little if anything is lost by this.
911 -- Do not do this test if errors have been detected, because in some
912 -- error cases, this code blows up, and we don't need it anyway if
913 -- there have been errors, since we won't get to the linker anyway.
915 if Serious_Errors_Detected = 0 then
918 P_Ent := Scope (P_Ent);
919 exit when No (P_Ent) or else P_Ent = Standard_Standard;
921 if Is_Subprogram (P_Ent) then
922 Set_Is_Inlined (P_Ent, False);
924 if Comes_From_Source (P_Ent)
925 and then Has_Pragma_Inline (P_Ent)
928 ("cannot inline& (nested subprogram)?",
935 -- Case of fully private operation in the body of the protected type.
936 -- We must create a declaration for the subprogram, in order to attach
937 -- the protected subprogram that will be used in internal calls.
940 and then Comes_From_Source (N)
941 and then Is_Protected_Type (Current_Scope)
950 Formal := First_Formal (Body_Id);
952 -- The protected operation always has at least one formal,
953 -- namely the object itself, but it is only placed in the
954 -- parameter list if expansion is enabled.
957 or else Expander_Active
965 while Present (Formal) loop
967 (Make_Parameter_Specification (Loc,
968 Defining_Identifier =>
969 Make_Defining_Identifier (Sloc (Formal),
970 Chars => Chars (Formal)),
971 In_Present => In_Present (Parent (Formal)),
972 Out_Present => Out_Present (Parent (Formal)),
974 New_Reference_To (Etype (Formal), Loc),
976 New_Copy_Tree (Expression (Parent (Formal)))),
979 Next_Formal (Formal);
982 if Nkind (Body_Spec) = N_Procedure_Specification then
984 Make_Procedure_Specification (Loc,
985 Defining_Unit_Name =>
986 Make_Defining_Identifier (Sloc (Body_Id),
987 Chars => Chars (Body_Id)),
988 Parameter_Specifications => Plist);
991 Make_Function_Specification (Loc,
992 Defining_Unit_Name =>
993 Make_Defining_Identifier (Sloc (Body_Id),
994 Chars => Chars (Body_Id)),
995 Parameter_Specifications => Plist,
996 Subtype_Mark => New_Occurrence_Of (Etype (Body_Id), Loc));
1000 Make_Subprogram_Declaration (Loc,
1001 Specification => New_Spec);
1002 Insert_Before (N, Decl);
1003 Spec_Id := Defining_Unit_Name (New_Spec);
1005 -- Indicate that the entity comes from source, to ensure that
1006 -- cross-reference information is properly generated.
1007 -- The body itself is rewritten during expansion, and the
1008 -- body entity will not appear in calls to the operation.
1010 Set_Comes_From_Source (Spec_Id, True);
1012 Set_Has_Completion (Spec_Id);
1013 Set_Convention (Spec_Id, Convention_Protected);
1016 elsif Present (Spec_Id) then
1017 Spec_Decl := Unit_Declaration_Node (Spec_Id);
1020 -- Place subprogram on scope stack, and make formals visible. If there
1021 -- is a spec, the visible entity remains that of the spec.
1023 if Present (Spec_Id) then
1024 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
1026 Style.Check_Identifier (Body_Id, Spec_Id);
1029 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
1030 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
1032 if Is_Abstract (Spec_Id) then
1033 Error_Msg_N ("an abstract subprogram cannot have a body", N);
1036 Set_Convention (Body_Id, Convention (Spec_Id));
1037 Set_Has_Completion (Spec_Id);
1039 if Is_Protected_Type (Scope (Spec_Id)) then
1040 Set_Privals_Chain (Spec_Id, New_Elmt_List);
1043 -- If this is a body generated for a renaming, do not check for
1044 -- full conformance. The check is redundant, because the spec of
1045 -- the body is a copy of the spec in the renaming declaration,
1046 -- and the test can lead to spurious errors on nested defaults.
1048 if Present (Spec_Decl)
1049 and then not Comes_From_Source (N)
1051 (Nkind (Original_Node (Spec_Decl)) =
1052 N_Subprogram_Renaming_Declaration
1053 or else (Present (Corresponding_Body (Spec_Decl))
1055 Nkind (Unit_Declaration_Node
1056 (Corresponding_Body (Spec_Decl))) =
1057 N_Subprogram_Renaming_Declaration))
1063 Fully_Conformant, True, Conformant, Body_Id);
1066 -- If the body is not fully conformant, we have to decide if we
1067 -- should analyze it or not. If it has a really messed up profile
1068 -- then we probably should not analyze it, since we will get too
1069 -- many bogus messages.
1071 -- Our decision is to go ahead in the non-fully conformant case
1072 -- only if it is at least mode conformant with the spec. Note
1073 -- that the call to Check_Fully_Conformant has issued the proper
1074 -- error messages to complain about the lack of conformance.
1077 and then not Mode_Conformant (Body_Id, Spec_Id)
1083 if Spec_Id /= Body_Id then
1084 Reference_Body_Formals (Spec_Id, Body_Id);
1087 if Nkind (N) /= N_Subprogram_Body_Stub then
1088 Set_Corresponding_Spec (N, Spec_Id);
1089 Install_Formals (Spec_Id);
1090 Last_Formal := Last_Entity (Spec_Id);
1091 New_Scope (Spec_Id);
1093 -- Make sure that the subprogram is immediately visible. For
1094 -- child units that have no separate spec this is indispensable.
1095 -- Otherwise it is safe albeit redundant.
1097 Set_Is_Immediately_Visible (Spec_Id);
1100 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
1101 Set_Ekind (Body_Id, E_Subprogram_Body);
1102 Set_Scope (Body_Id, Scope (Spec_Id));
1104 -- Case of subprogram body with no previous spec
1108 and then Comes_From_Source (Body_Id)
1109 and then not Suppress_Style_Checks (Body_Id)
1110 and then not In_Instance
1112 Style.Body_With_No_Spec (N);
1115 New_Overloaded_Entity (Body_Id);
1117 if Nkind (N) /= N_Subprogram_Body_Stub then
1118 Set_Acts_As_Spec (N);
1119 Generate_Definition (Body_Id);
1121 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
1122 Generate_Reference_To_Formals (Body_Id);
1123 Install_Formals (Body_Id);
1124 New_Scope (Body_Id);
1128 -- If this is the proper body of a stub, we must verify that the stub
1129 -- conforms to the body, and to the previous spec if one was present.
1130 -- we know already that the body conforms to that spec. This test is
1131 -- only required for subprograms that come from source.
1133 if Nkind (Parent (N)) = N_Subunit
1134 and then Comes_From_Source (N)
1135 and then not Error_Posted (Body_Id)
1138 Old_Id : constant Entity_Id :=
1140 (Specification (Corresponding_Stub (Parent (N))));
1142 Conformant : Boolean := False;
1145 if No (Spec_Id) then
1146 Check_Fully_Conformant (Body_Id, Old_Id);
1150 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
1152 if not Conformant then
1154 -- The stub was taken to be a new declaration. Indicate
1155 -- that it lacks a body.
1157 Set_Has_Completion (Old_Id, False);
1163 Set_Has_Completion (Body_Id);
1164 Check_Eliminated (Body_Id);
1166 if Nkind (N) = N_Subprogram_Body_Stub then
1169 elsif Present (Spec_Id)
1170 and then Expander_Active
1172 Check_Following_Pragma;
1174 if Is_Always_Inlined (Spec_Id)
1175 or else (Has_Pragma_Inline (Spec_Id)
1176 and then (Front_End_Inlining or else Configurable_Run_Time_Mode))
1178 Build_Body_To_Inline (N, Spec_Id);
1182 -- Ada 0Y (AI-262): In library subprogram bodies, after the analysis
1183 -- if its specification we have to install the private withed units.
1185 if Is_Compilation_Unit (Body_Id)
1186 and then Scope (Body_Id) = Standard_Standard
1188 Install_Private_With_Clauses (Body_Id);
1191 -- Now we can go on to analyze the body
1193 HSS := Handled_Statement_Sequence (N);
1194 Set_Actual_Subtypes (N, Current_Scope);
1195 Analyze_Declarations (Declarations (N));
1198 Process_End_Label (HSS, 't', Current_Scope);
1200 Check_Subprogram_Order (N);
1201 Set_Analyzed (Body_Id);
1203 -- If we have a separate spec, then the analysis of the declarations
1204 -- caused the entities in the body to be chained to the spec id, but
1205 -- we want them chained to the body id. Only the formal parameters
1206 -- end up chained to the spec id in this case.
1208 if Present (Spec_Id) then
1210 -- If a parent unit is categorized, the context of a subunit
1211 -- must conform to the categorization. Conversely, if a child
1212 -- unit is categorized, the parents themselves must conform.
1214 if Nkind (Parent (N)) = N_Subunit then
1215 Validate_Categorization_Dependency (N, Spec_Id);
1217 elsif Is_Child_Unit (Spec_Id) then
1218 Validate_Categorization_Dependency
1219 (Unit_Declaration_Node (Spec_Id), Spec_Id);
1222 if Present (Last_Formal) then
1224 (Last_Entity (Body_Id), Next_Entity (Last_Formal));
1225 Set_Next_Entity (Last_Formal, Empty);
1226 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
1227 Set_Last_Entity (Spec_Id, Last_Formal);
1230 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
1231 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
1232 Set_First_Entity (Spec_Id, Empty);
1233 Set_Last_Entity (Spec_Id, Empty);
1237 -- If function, check return statements
1239 if Nkind (Body_Spec) = N_Function_Specification then
1244 if Present (Spec_Id) then
1250 if Return_Present (Id) then
1251 Check_Returns (HSS, 'F', Missing_Ret);
1254 Set_Has_Missing_Return (Id);
1257 elsif not Is_Machine_Code_Subprogram (Id)
1258 and then not Body_Deleted
1260 Error_Msg_N ("missing RETURN statement in function body", N);
1264 -- If procedure with No_Return, check returns
1266 elsif Nkind (Body_Spec) = N_Procedure_Specification
1267 and then Present (Spec_Id)
1268 and then No_Return (Spec_Id)
1270 Check_Returns (HSS, 'P', Missing_Ret);
1273 -- Now we are going to check for variables that are never modified
1274 -- in the body of the procedure. We omit these checks if the first
1275 -- statement of the procedure raises an exception. In particular
1276 -- this deals with the common idiom of a stubbed function, which
1277 -- might appear as something like
1279 -- function F (A : Integer) return Some_Type;
1282 -- raise Program_Error;
1286 -- Here the purpose of X is simply to satisfy the (annoying)
1287 -- requirement in Ada that there be at least one return, and
1288 -- we certainly do not want to go posting warnings on X that
1289 -- it is not initialized!
1292 Stm : Node_Id := First (Statements (HSS));
1295 -- Skip an initial label (for one thing this occurs when we
1296 -- are in front end ZCX mode, but in any case it is irrelevant).
1298 if Nkind (Stm) = N_Label then
1302 -- Do the test on the original statement before expansion
1305 Ostm : constant Node_Id := Original_Node (Stm);
1308 -- If explicit raise statement, return with no checks
1310 if Nkind (Ostm) = N_Raise_Statement then
1313 -- Check for explicit call cases which likely raise an exception
1315 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
1316 if Is_Entity_Name (Name (Ostm)) then
1318 Ent : constant Entity_Id := Entity (Name (Ostm));
1321 -- If the procedure is marked No_Return, then likely it
1322 -- raises an exception, but in any case it is not coming
1323 -- back here, so no need to check beyond the call.
1325 if Ekind (Ent) = E_Procedure
1326 and then No_Return (Ent)
1330 -- If the procedure name is Raise_Exception, then also
1331 -- assume that it raises an exception. The main target
1332 -- here is Ada.Exceptions.Raise_Exception, but this name
1333 -- is pretty evocative in any context! Note that the
1334 -- procedure in Ada.Exceptions is not marked No_Return
1335 -- because of the annoying case of the null exception Id.
1337 elsif Chars (Ent) = Name_Raise_Exception then
1346 -- Check for variables that are never modified
1352 -- If there is a separate spec, then transfer Never_Set_In_Source
1353 -- flags from out parameters to the corresponding entities in the
1354 -- body. The reason we do that is we want to post error flags on
1355 -- the body entities, not the spec entities.
1357 if Present (Spec_Id) then
1358 E1 := First_Entity (Spec_Id);
1360 while Present (E1) loop
1361 if Ekind (E1) = E_Out_Parameter then
1362 E2 := First_Entity (Body_Id);
1363 while Present (E2) loop
1364 exit when Chars (E1) = Chars (E2);
1368 if Present (E2) then
1369 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
1377 -- Check references in body unless it was deleted. Note that the
1378 -- check of Body_Deleted here is not just for efficiency, it is
1379 -- necessary to avoid junk warnings on formal parameters.
1381 if not Body_Deleted then
1382 Check_References (Body_Id);
1385 end Analyze_Subprogram_Body;
1387 ------------------------------------
1388 -- Analyze_Subprogram_Declaration --
1389 ------------------------------------
1391 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
1392 Designator : constant Entity_Id :=
1393 Analyze_Subprogram_Specification (Specification (N));
1394 Scop : constant Entity_Id := Current_Scope;
1396 -- Start of processing for Analyze_Subprogram_Declaration
1399 Generate_Definition (Designator);
1401 -- Check for RCI unit subprogram declarations against in-lined
1402 -- subprograms and subprograms having access parameter or limited
1403 -- parameter without Read and Write (RM E.2.3(12-13)).
1405 Validate_RCI_Subprogram_Declaration (N);
1409 Defining_Entity (N),
1410 " Analyze subprogram spec. ");
1412 if Debug_Flag_C then
1413 Write_Str ("==== Compiling subprogram spec ");
1414 Write_Name (Chars (Designator));
1415 Write_Str (" from ");
1416 Write_Location (Sloc (N));
1420 New_Overloaded_Entity (Designator);
1421 Check_Delayed_Subprogram (Designator);
1423 -- What is the following code for, it used to be
1425 -- ??? Set_Suppress_Elaboration_Checks
1426 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
1428 -- The following seems equivalent, but a bit dubious
1430 if Elaboration_Checks_Suppressed (Designator) then
1431 Set_Kill_Elaboration_Checks (Designator);
1434 if Scop /= Standard_Standard
1435 and then not Is_Child_Unit (Designator)
1437 Set_Categorization_From_Scope (Designator, Scop);
1439 -- For a compilation unit, check for library-unit pragmas.
1441 New_Scope (Designator);
1442 Set_Categorization_From_Pragmas (N);
1443 Validate_Categorization_Dependency (N, Designator);
1447 -- For a compilation unit, set body required. This flag will only be
1448 -- reset if a valid Import or Interface pragma is processed later on.
1450 if Nkind (Parent (N)) = N_Compilation_Unit then
1451 Set_Body_Required (Parent (N), True);
1454 Generate_Reference_To_Formals (Designator);
1455 Check_Eliminated (Designator);
1457 if Comes_From_Source (N)
1458 and then Is_List_Member (N)
1460 Check_Overriding_Operation (N, Designator);
1463 end Analyze_Subprogram_Declaration;
1465 --------------------------------------
1466 -- Analyze_Subprogram_Specification --
1467 --------------------------------------
1469 -- Reminder: N here really is a subprogram specification (not a subprogram
1470 -- declaration). This procedure is called to analyze the specification in
1471 -- both subprogram bodies and subprogram declarations (specs).
1473 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
1474 Designator : constant Entity_Id := Defining_Entity (N);
1475 Formals : constant List_Id := Parameter_Specifications (N);
1479 Generate_Definition (Designator);
1481 if Nkind (N) = N_Function_Specification then
1482 Set_Ekind (Designator, E_Function);
1483 Set_Mechanism (Designator, Default_Mechanism);
1485 if Subtype_Mark (N) /= Error then
1486 Find_Type (Subtype_Mark (N));
1487 Typ := Entity (Subtype_Mark (N));
1488 Set_Etype (Designator, Typ);
1490 if Ekind (Typ) = E_Incomplete_Type
1491 or else (Is_Class_Wide_Type (Typ)
1493 Ekind (Root_Type (Typ)) = E_Incomplete_Type)
1496 ("invalid use of incomplete type", Subtype_Mark (N));
1500 Set_Etype (Designator, Any_Type);
1504 Set_Ekind (Designator, E_Procedure);
1505 Set_Etype (Designator, Standard_Void_Type);
1508 if Present (Formals) then
1509 Set_Scope (Designator, Current_Scope);
1510 New_Scope (Designator);
1511 Process_Formals (Formals, N);
1515 if Nkind (N) = N_Function_Specification then
1516 if Nkind (Designator) = N_Defining_Operator_Symbol then
1517 Valid_Operator_Definition (Designator);
1520 May_Need_Actuals (Designator);
1522 if Is_Abstract (Etype (Designator))
1523 and then Nkind (Parent (N)) /= N_Abstract_Subprogram_Declaration
1526 ("function that returns abstract type must be abstract", N);
1531 end Analyze_Subprogram_Specification;
1533 --------------------------
1534 -- Build_Body_To_Inline --
1535 --------------------------
1537 procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id) is
1538 Decl : constant Node_Id := Unit_Declaration_Node (Subp);
1539 Original_Body : Node_Id;
1540 Body_To_Analyze : Node_Id;
1541 Max_Size : constant := 10;
1542 Stat_Count : Integer := 0;
1544 function Has_Excluded_Declaration (Decls : List_Id) return Boolean;
1545 -- Check for declarations that make inlining not worthwhile.
1547 function Has_Excluded_Statement (Stats : List_Id) return Boolean;
1548 -- Check for statements that make inlining not worthwhile: any
1549 -- tasking statement, nested at any level. Keep track of total
1550 -- number of elementary statements, as a measure of acceptable size.
1552 function Has_Pending_Instantiation return Boolean;
1553 -- If some enclosing body contains instantiations that appear before
1554 -- the corresponding generic body, the enclosing body has a freeze node
1555 -- so that it can be elaborated after the generic itself. This might
1556 -- conflict with subsequent inlinings, so that it is unsafe to try to
1557 -- inline in such a case.
1559 procedure Remove_Pragmas;
1560 -- A pragma Unreferenced that mentions a formal parameter has no
1561 -- meaning when the body is inlined and the formals are rewritten.
1562 -- Remove it from body to inline. The analysis of the non-inlined
1563 -- body will handle the pragma properly.
1565 ------------------------------
1566 -- Has_Excluded_Declaration --
1567 ------------------------------
1569 function Has_Excluded_Declaration (Decls : List_Id) return Boolean is
1572 function Is_Unchecked_Conversion (D : Node_Id) return Boolean;
1573 -- Nested subprograms make a given body ineligible for inlining,
1574 -- but we make an exception for instantiations of unchecked
1575 -- conversion. The body has not been analyzed yet, so we check
1576 -- the name, and verify that the visible entity with that name is
1577 -- the predefined unit.
1579 function Is_Unchecked_Conversion (D : Node_Id) return Boolean is
1580 Id : constant Node_Id := Name (D);
1584 if Nkind (Id) = N_Identifier
1585 and then Chars (Id) = Name_Unchecked_Conversion
1587 Conv := Current_Entity (Id);
1589 elsif Nkind (Id) = N_Selected_Component
1590 and then Chars (Selector_Name (Id)) = Name_Unchecked_Conversion
1592 Conv := Current_Entity (Selector_Name (Id));
1600 and then Scope (Conv) = Standard_Standard
1601 and then Is_Intrinsic_Subprogram (Conv);
1602 end Is_Unchecked_Conversion;
1604 -- Start of processing for Has_Excluded_Declaration
1609 while Present (D) loop
1610 if (Nkind (D) = N_Function_Instantiation
1611 and then not Is_Unchecked_Conversion (D))
1612 or else Nkind (D) = N_Protected_Type_Declaration
1613 or else Nkind (D) = N_Package_Declaration
1614 or else Nkind (D) = N_Package_Instantiation
1615 or else Nkind (D) = N_Subprogram_Body
1616 or else Nkind (D) = N_Procedure_Instantiation
1617 or else Nkind (D) = N_Task_Type_Declaration
1620 ("cannot inline & (non-allowed declaration)?", D, Subp);
1628 end Has_Excluded_Declaration;
1630 ----------------------------
1631 -- Has_Excluded_Statement --
1632 ----------------------------
1634 function Has_Excluded_Statement (Stats : List_Id) return Boolean is
1641 while Present (S) loop
1642 Stat_Count := Stat_Count + 1;
1644 if Nkind (S) = N_Abort_Statement
1645 or else Nkind (S) = N_Asynchronous_Select
1646 or else Nkind (S) = N_Conditional_Entry_Call
1647 or else Nkind (S) = N_Delay_Relative_Statement
1648 or else Nkind (S) = N_Delay_Until_Statement
1649 or else Nkind (S) = N_Selective_Accept
1650 or else Nkind (S) = N_Timed_Entry_Call
1653 ("cannot inline & (non-allowed statement)?", S, Subp);
1656 elsif Nkind (S) = N_Block_Statement then
1657 if Present (Declarations (S))
1658 and then Has_Excluded_Declaration (Declarations (S))
1662 elsif Present (Handled_Statement_Sequence (S))
1665 (Exception_Handlers (Handled_Statement_Sequence (S)))
1667 Has_Excluded_Statement
1668 (Statements (Handled_Statement_Sequence (S))))
1673 elsif Nkind (S) = N_Case_Statement then
1674 E := First (Alternatives (S));
1676 while Present (E) loop
1677 if Has_Excluded_Statement (Statements (E)) then
1684 elsif Nkind (S) = N_If_Statement then
1685 if Has_Excluded_Statement (Then_Statements (S)) then
1689 if Present (Elsif_Parts (S)) then
1690 E := First (Elsif_Parts (S));
1692 while Present (E) loop
1693 if Has_Excluded_Statement (Then_Statements (E)) then
1700 if Present (Else_Statements (S))
1701 and then Has_Excluded_Statement (Else_Statements (S))
1706 elsif Nkind (S) = N_Loop_Statement
1707 and then Has_Excluded_Statement (Statements (S))
1716 end Has_Excluded_Statement;
1718 -------------------------------
1719 -- Has_Pending_Instantiation --
1720 -------------------------------
1722 function Has_Pending_Instantiation return Boolean is
1723 S : Entity_Id := Current_Scope;
1726 while Present (S) loop
1727 if Is_Compilation_Unit (S)
1728 or else Is_Child_Unit (S)
1731 elsif Ekind (S) = E_Package
1732 and then Has_Forward_Instantiation (S)
1741 end Has_Pending_Instantiation;
1743 --------------------
1744 -- Remove_Pragmas --
1745 --------------------
1747 procedure Remove_Pragmas is
1752 Decl := First (Declarations (Body_To_Analyze));
1753 while Present (Decl) loop
1756 if Nkind (Decl) = N_Pragma
1757 and then Chars (Decl) = Name_Unreferenced
1766 -- Start of processing for Build_Body_To_Inline
1769 if Nkind (Decl) = N_Subprogram_Declaration
1770 and then Present (Body_To_Inline (Decl))
1772 return; -- Done already.
1774 -- Functions that return unconstrained composite types will require
1775 -- secondary stack handling, and cannot currently be inlined.
1776 -- Ditto for functions that return controlled types, where controlled
1777 -- actions interfere in complex ways with inlining.
1779 elsif Ekind (Subp) = E_Function
1780 and then not Is_Scalar_Type (Etype (Subp))
1781 and then not Is_Access_Type (Etype (Subp))
1782 and then not Is_Constrained (Etype (Subp))
1785 ("cannot inline & (unconstrained return type)?", N, Subp);
1788 elsif Ekind (Subp) = E_Function
1789 and then Controlled_Type (Etype (Subp))
1792 ("cannot inline & (controlled return type)?", N, Subp);
1796 if Present (Declarations (N))
1797 and then Has_Excluded_Declaration (Declarations (N))
1802 if Present (Handled_Statement_Sequence (N)) then
1803 if Present (Exception_Handlers (Handled_Statement_Sequence (N))) then
1805 ("cannot inline& (exception handler)?",
1806 First (Exception_Handlers (Handled_Statement_Sequence (N))),
1810 Has_Excluded_Statement
1811 (Statements (Handled_Statement_Sequence (N)))
1817 -- We do not inline a subprogram that is too large, unless it is
1818 -- marked Inline_Always. This pragma does not suppress the other
1819 -- checks on inlining (forbidden declarations, handlers, etc).
1821 if Stat_Count > Max_Size
1822 and then not Is_Always_Inlined (Subp)
1824 Cannot_Inline ("cannot inline& (body too large)?", N, Subp);
1828 if Has_Pending_Instantiation then
1830 ("cannot inline& (forward instance within enclosing body)?",
1835 -- Within an instance, the body to inline must be treated as a nested
1836 -- generic, so that the proper global references are preserved.
1839 Save_Env (Scope (Current_Scope), Scope (Current_Scope));
1840 Original_Body := Copy_Generic_Node (N, Empty, True);
1842 Original_Body := Copy_Separate_Tree (N);
1845 -- We need to capture references to the formals in order to substitute
1846 -- the actuals at the point of inlining, i.e. instantiation. To treat
1847 -- the formals as globals to the body to inline, we nest it within
1848 -- a dummy parameterless subprogram, declared within the real one.
1849 -- To avoid generating an internal name (which is never public, and
1850 -- which affects serial numbers of other generated names), we use
1851 -- an internal symbol that cannot conflict with user declarations.
1853 Set_Parameter_Specifications (Specification (Original_Body), No_List);
1854 Set_Defining_Unit_Name
1855 (Specification (Original_Body),
1856 Make_Defining_Identifier (Sloc (N), Name_uParent));
1857 Set_Corresponding_Spec (Original_Body, Empty);
1859 Body_To_Analyze := Copy_Generic_Node (Original_Body, Empty, False);
1861 -- Set return type of function, which is also global and does not need
1864 if Ekind (Subp) = E_Function then
1865 Set_Subtype_Mark (Specification (Body_To_Analyze),
1866 New_Occurrence_Of (Etype (Subp), Sloc (N)));
1869 if No (Declarations (N)) then
1870 Set_Declarations (N, New_List (Body_To_Analyze));
1872 Append (Body_To_Analyze, Declarations (N));
1875 Expander_Mode_Save_And_Set (False);
1878 Analyze (Body_To_Analyze);
1879 New_Scope (Defining_Entity (Body_To_Analyze));
1880 Save_Global_References (Original_Body);
1882 Remove (Body_To_Analyze);
1884 Expander_Mode_Restore;
1885 Set_Body_To_Inline (Decl, Original_Body);
1886 Set_Ekind (Defining_Entity (Original_Body), Ekind (Subp));
1887 Set_Is_Inlined (Subp);
1892 end Build_Body_To_Inline;
1898 procedure Cannot_Inline (Msg : String; N : Node_Id; Subp : Entity_Id) is
1900 -- Do not emit warning if this is a predefined unit which is not
1901 -- the main unit. With validity checks enabled, some predefined
1902 -- subprograms may contain nested subprograms and become ineligible
1905 if Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (Subp)))
1906 and then not In_Extended_Main_Source_Unit (Subp)
1910 elsif Is_Always_Inlined (Subp) then
1911 Error_Msg_NE (Msg (1 .. Msg'Length - 1), N, Subp);
1913 elsif Ineffective_Inline_Warnings then
1914 Error_Msg_NE (Msg, N, Subp);
1918 -----------------------
1919 -- Check_Conformance --
1920 -----------------------
1922 procedure Check_Conformance
1923 (New_Id : Entity_Id;
1925 Ctype : Conformance_Type;
1927 Conforms : out Boolean;
1928 Err_Loc : Node_Id := Empty;
1929 Get_Inst : Boolean := False)
1931 Old_Type : constant Entity_Id := Etype (Old_Id);
1932 New_Type : constant Entity_Id := Etype (New_Id);
1933 Old_Formal : Entity_Id;
1934 New_Formal : Entity_Id;
1936 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
1937 -- Post error message for conformance error on given node.
1938 -- Two messages are output. The first points to the previous
1939 -- declaration with a general "no conformance" message.
1940 -- The second is the detailed reason, supplied as Msg. The
1941 -- parameter N provide information for a possible & insertion
1942 -- in the message, and also provides the location for posting
1943 -- the message in the absence of a specified Err_Loc location.
1945 -----------------------
1946 -- Conformance_Error --
1947 -----------------------
1949 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
1956 if No (Err_Loc) then
1962 Error_Msg_Sloc := Sloc (Old_Id);
1965 when Type_Conformant =>
1967 ("not type conformant with declaration#!", Enode);
1969 when Mode_Conformant =>
1971 ("not mode conformant with declaration#!", Enode);
1973 when Subtype_Conformant =>
1975 ("not subtype conformant with declaration#!", Enode);
1977 when Fully_Conformant =>
1979 ("not fully conformant with declaration#!", Enode);
1982 Error_Msg_NE (Msg, Enode, N);
1984 end Conformance_Error;
1986 -- Start of processing for Check_Conformance
1991 -- We need a special case for operators, since they don't
1992 -- appear explicitly.
1994 if Ctype = Type_Conformant then
1995 if Ekind (New_Id) = E_Operator
1996 and then Operator_Matches_Spec (New_Id, Old_Id)
2002 -- If both are functions/operators, check return types conform
2004 if Old_Type /= Standard_Void_Type
2005 and then New_Type /= Standard_Void_Type
2007 if not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
2008 Conformance_Error ("return type does not match!", New_Id);
2012 -- If either is a function/operator and the other isn't, error
2014 elsif Old_Type /= Standard_Void_Type
2015 or else New_Type /= Standard_Void_Type
2017 Conformance_Error ("functions can only match functions!", New_Id);
2021 -- In subtype conformant case, conventions must match (RM 6.3.1(16))
2022 -- If this is a renaming as body, refine error message to indicate that
2023 -- the conflict is with the original declaration. If the entity is not
2024 -- frozen, the conventions don't have to match, the one of the renamed
2025 -- entity is inherited.
2027 if Ctype >= Subtype_Conformant then
2028 if Convention (Old_Id) /= Convention (New_Id) then
2030 if not Is_Frozen (New_Id) then
2033 elsif Present (Err_Loc)
2034 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
2035 and then Present (Corresponding_Spec (Err_Loc))
2037 Error_Msg_Name_1 := Chars (New_Id);
2039 Name_Ada + Convention_Id'Pos (Convention (New_Id));
2041 Conformance_Error ("prior declaration for% has convention %!");
2044 Conformance_Error ("calling conventions do not match!");
2049 elsif Is_Formal_Subprogram (Old_Id)
2050 or else Is_Formal_Subprogram (New_Id)
2052 Conformance_Error ("formal subprograms not allowed!");
2057 -- Deal with parameters
2059 -- Note: we use the entity information, rather than going directly
2060 -- to the specification in the tree. This is not only simpler, but
2061 -- absolutely necessary for some cases of conformance tests between
2062 -- operators, where the declaration tree simply does not exist!
2064 Old_Formal := First_Formal (Old_Id);
2065 New_Formal := First_Formal (New_Id);
2067 while Present (Old_Formal) and then Present (New_Formal) loop
2068 if Ctype = Fully_Conformant then
2070 -- Names must match. Error message is more accurate if we do
2071 -- this before checking that the types of the formals match.
2073 if Chars (Old_Formal) /= Chars (New_Formal) then
2074 Conformance_Error ("name & does not match!", New_Formal);
2076 -- Set error posted flag on new formal as well to stop
2077 -- junk cascaded messages in some cases.
2079 Set_Error_Posted (New_Formal);
2084 -- Types must always match. In the visible part of an instance,
2085 -- usual overloading rules for dispatching operations apply, and
2086 -- we check base types (not the actual subtypes).
2088 if In_Instance_Visible_Part
2089 and then Is_Dispatching_Operation (New_Id)
2091 if not Conforming_Types
2092 (Base_Type (Etype (Old_Formal)),
2093 Base_Type (Etype (New_Formal)), Ctype, Get_Inst)
2095 Conformance_Error ("type of & does not match!", New_Formal);
2099 elsif not Conforming_Types
2100 (Etype (Old_Formal), Etype (New_Formal), Ctype, Get_Inst)
2102 Conformance_Error ("type of & does not match!", New_Formal);
2106 -- For mode conformance, mode must match
2108 if Ctype >= Mode_Conformant
2109 and then Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal)
2111 Conformance_Error ("mode of & does not match!", New_Formal);
2115 -- Full conformance checks
2117 if Ctype = Fully_Conformant then
2119 -- We have checked already that names match.
2120 -- Check default expressions for in parameters
2122 if Parameter_Mode (Old_Formal) = E_In_Parameter then
2124 NewD : constant Boolean :=
2125 Present (Default_Value (New_Formal));
2126 OldD : constant Boolean :=
2127 Present (Default_Value (Old_Formal));
2129 if NewD or OldD then
2131 -- The old default value has been analyzed because
2132 -- the current full declaration will have frozen
2133 -- everything before. The new default values have not
2134 -- been analyzed, so analyze them now before we check
2139 Analyze_Per_Use_Expression
2140 (Default_Value (New_Formal), Etype (New_Formal));
2144 if not (NewD and OldD)
2145 or else not Fully_Conformant_Expressions
2146 (Default_Value (Old_Formal),
2147 Default_Value (New_Formal))
2150 ("default expression for & does not match!",
2159 -- A couple of special checks for Ada 83 mode. These checks are
2160 -- skipped if either entity is an operator in package Standard.
2161 -- or if either old or new instance is not from the source program.
2164 and then Sloc (Old_Id) > Standard_Location
2165 and then Sloc (New_Id) > Standard_Location
2166 and then Comes_From_Source (Old_Id)
2167 and then Comes_From_Source (New_Id)
2170 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
2171 New_Param : constant Node_Id := Declaration_Node (New_Formal);
2174 -- Explicit IN must be present or absent in both cases. This
2175 -- test is required only in the full conformance case.
2177 if In_Present (Old_Param) /= In_Present (New_Param)
2178 and then Ctype = Fully_Conformant
2181 ("(Ada 83) IN must appear in both declarations",
2186 -- Grouping (use of comma in param lists) must be the same
2187 -- This is where we catch a misconformance like:
2190 -- A : Integer; B : Integer
2192 -- which are represented identically in the tree except
2193 -- for the setting of the flags More_Ids and Prev_Ids.
2195 if More_Ids (Old_Param) /= More_Ids (New_Param)
2196 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
2199 ("grouping of & does not match!", New_Formal);
2205 Next_Formal (Old_Formal);
2206 Next_Formal (New_Formal);
2209 if Present (Old_Formal) then
2210 Conformance_Error ("too few parameters!");
2213 elsif Present (New_Formal) then
2214 Conformance_Error ("too many parameters!", New_Formal);
2218 end Check_Conformance;
2220 ------------------------------
2221 -- Check_Delayed_Subprogram --
2222 ------------------------------
2224 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
2227 procedure Possible_Freeze (T : Entity_Id);
2228 -- T is the type of either a formal parameter or of the return type.
2229 -- If T is not yet frozen and needs a delayed freeze, then the
2230 -- subprogram itself must be delayed.
2232 procedure Possible_Freeze (T : Entity_Id) is
2234 if Has_Delayed_Freeze (T)
2235 and then not Is_Frozen (T)
2237 Set_Has_Delayed_Freeze (Designator);
2239 elsif Is_Access_Type (T)
2240 and then Has_Delayed_Freeze (Designated_Type (T))
2241 and then not Is_Frozen (Designated_Type (T))
2243 Set_Has_Delayed_Freeze (Designator);
2245 end Possible_Freeze;
2247 -- Start of processing for Check_Delayed_Subprogram
2250 -- Never need to freeze abstract subprogram
2252 if Is_Abstract (Designator) then
2255 -- Need delayed freeze if return type itself needs a delayed
2256 -- freeze and is not yet frozen.
2258 Possible_Freeze (Etype (Designator));
2259 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
2261 -- Need delayed freeze if any of the formal types themselves need
2262 -- a delayed freeze and are not yet frozen.
2264 F := First_Formal (Designator);
2265 while Present (F) loop
2266 Possible_Freeze (Etype (F));
2267 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
2272 -- Mark functions that return by reference. Note that it cannot be
2273 -- done for delayed_freeze subprograms because the underlying
2274 -- returned type may not be known yet (for private types)
2276 if not Has_Delayed_Freeze (Designator)
2277 and then Expander_Active
2280 Typ : constant Entity_Id := Etype (Designator);
2281 Utyp : constant Entity_Id := Underlying_Type (Typ);
2284 if Is_Return_By_Reference_Type (Typ) then
2285 Set_Returns_By_Ref (Designator);
2287 elsif Present (Utyp) and then Controlled_Type (Utyp) then
2288 Set_Returns_By_Ref (Designator);
2292 end Check_Delayed_Subprogram;
2294 ------------------------------------
2295 -- Check_Discriminant_Conformance --
2296 ------------------------------------
2298 procedure Check_Discriminant_Conformance
2303 Old_Discr : Entity_Id := First_Discriminant (Prev);
2304 New_Discr : Node_Id := First (Discriminant_Specifications (N));
2305 New_Discr_Id : Entity_Id;
2306 New_Discr_Type : Entity_Id;
2308 procedure Conformance_Error (Msg : String; N : Node_Id);
2309 -- Post error message for conformance error on given node.
2310 -- Two messages are output. The first points to the previous
2311 -- declaration with a general "no conformance" message.
2312 -- The second is the detailed reason, supplied as Msg. The
2313 -- parameter N provide information for a possible & insertion
2316 -----------------------
2317 -- Conformance_Error --
2318 -----------------------
2320 procedure Conformance_Error (Msg : String; N : Node_Id) is
2322 Error_Msg_Sloc := Sloc (Prev_Loc);
2323 Error_Msg_N ("not fully conformant with declaration#!", N);
2324 Error_Msg_NE (Msg, N, N);
2325 end Conformance_Error;
2327 -- Start of processing for Check_Discriminant_Conformance
2330 while Present (Old_Discr) and then Present (New_Discr) loop
2332 New_Discr_Id := Defining_Identifier (New_Discr);
2334 -- The subtype mark of the discriminant on the full type
2335 -- has not been analyzed so we do it here. For an access
2336 -- discriminant a new type is created.
2338 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
2340 Access_Definition (N, Discriminant_Type (New_Discr));
2343 Analyze (Discriminant_Type (New_Discr));
2344 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
2347 if not Conforming_Types
2348 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
2350 Conformance_Error ("type of & does not match!", New_Discr_Id);
2353 -- Treat the new discriminant as an occurrence of the old
2354 -- one, for navigation purposes, and fill in some semantic
2355 -- information, for completeness.
2357 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
2358 Set_Etype (New_Discr_Id, Etype (Old_Discr));
2359 Set_Scope (New_Discr_Id, Scope (Old_Discr));
2364 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
2365 Conformance_Error ("name & does not match!", New_Discr_Id);
2369 -- Default expressions must match
2372 NewD : constant Boolean :=
2373 Present (Expression (New_Discr));
2374 OldD : constant Boolean :=
2375 Present (Expression (Parent (Old_Discr)));
2378 if NewD or OldD then
2380 -- The old default value has been analyzed and expanded,
2381 -- because the current full declaration will have frozen
2382 -- everything before. The new default values have not
2383 -- been expanded, so expand now to check conformance.
2386 Analyze_Per_Use_Expression
2387 (Expression (New_Discr), New_Discr_Type);
2390 if not (NewD and OldD)
2391 or else not Fully_Conformant_Expressions
2392 (Expression (Parent (Old_Discr)),
2393 Expression (New_Discr))
2397 ("default expression for & does not match!",
2404 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
2408 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
2411 -- Grouping (use of comma in param lists) must be the same
2412 -- This is where we catch a misconformance like:
2415 -- A : Integer; B : Integer
2417 -- which are represented identically in the tree except
2418 -- for the setting of the flags More_Ids and Prev_Ids.
2420 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
2421 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
2424 ("grouping of & does not match!", New_Discr_Id);
2430 Next_Discriminant (Old_Discr);
2434 if Present (Old_Discr) then
2435 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
2438 elsif Present (New_Discr) then
2440 ("too many discriminants!", Defining_Identifier (New_Discr));
2443 end Check_Discriminant_Conformance;
2445 ----------------------------
2446 -- Check_Fully_Conformant --
2447 ----------------------------
2449 procedure Check_Fully_Conformant
2450 (New_Id : Entity_Id;
2452 Err_Loc : Node_Id := Empty)
2458 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
2459 end Check_Fully_Conformant;
2461 ---------------------------
2462 -- Check_Mode_Conformant --
2463 ---------------------------
2465 procedure Check_Mode_Conformant
2466 (New_Id : Entity_Id;
2468 Err_Loc : Node_Id := Empty;
2469 Get_Inst : Boolean := False)
2475 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
2476 end Check_Mode_Conformant;
2478 --------------------------------
2479 -- Check_Overriding_Operation --
2480 --------------------------------
2482 procedure Check_Overriding_Operation
2488 Has_Pragma : Boolean := False;
2491 -- See whether there is an overriding pragma immediately following
2492 -- the declaration. Intervening pragmas, such as Inline, are allowed.
2495 while Present (Decl)
2496 and then Nkind (Decl) = N_Pragma
2498 if Chars (Decl) = Name_Overriding
2499 or else Chars (Decl) = Name_Optional_Overriding
2501 -- For now disable the use of these pragmas, until the ARG
2502 -- finalizes the design of this feature.
2504 Error_Msg_N ("?unrecognized pragma", Decl);
2506 if not Is_Overriding_Operation (Subp) then
2508 -- Before emitting an error message, check whether this
2509 -- may override an operation that is not yet visible, as
2510 -- in the case of a derivation of a private operation in
2511 -- a child unit. Such an operation is introduced with a
2512 -- different name, but its alias is the parent operation.
2518 E := First_Entity (Current_Scope);
2520 while Present (E) loop
2521 if Ekind (E) = Ekind (Subp)
2522 and then not Comes_From_Source (E)
2523 and then Present (Alias (E))
2524 and then Chars (Alias (E)) = Chars (Subp)
2525 and then In_Open_Scopes (Scope (Alias (E)))
2535 ("& must override an inherited operation",
2541 -- Verify syntax of pragma
2543 Arg1 := First (Pragma_Argument_Associations (Decl));
2545 if Present (Arg1) then
2546 if not Is_Entity_Name (Expression (Arg1)) then
2547 Error_Msg_N ("pragma applies to local subprogram", Decl);
2549 elsif Chars (Expression (Arg1)) /= Chars (Subp) then
2551 ("pragma must apply to preceding subprogram", Decl);
2553 elsif Present (Next (Arg1)) then
2554 Error_Msg_N ("illegal pragma format", Decl);
2558 Set_Analyzed (Decl);
2567 and then Explicit_Overriding
2568 and then Is_Overriding_Operation (Subp)
2570 Error_Msg_NE ("Missing overriding pragma for&", Subp, Subp);
2572 end Check_Overriding_Operation;
2578 procedure Check_Returns
2585 procedure Check_Statement_Sequence (L : List_Id);
2586 -- Internal recursive procedure to check a list of statements for proper
2587 -- termination by a return statement (or a transfer of control or a
2588 -- compound statement that is itself internally properly terminated).
2590 ------------------------------
2591 -- Check_Statement_Sequence --
2592 ------------------------------
2594 procedure Check_Statement_Sequence (L : List_Id) is
2598 Raise_Exception_Call : Boolean;
2599 -- Set True if statement sequence terminated by Raise_Exception call
2600 -- or a Reraise_Occurrence call.
2603 Raise_Exception_Call := False;
2605 -- Get last real statement
2607 Last_Stm := Last (L);
2609 -- Don't count pragmas
2611 while Nkind (Last_Stm) = N_Pragma
2613 -- Don't count call to SS_Release (can happen after Raise_Exception)
2616 (Nkind (Last_Stm) = N_Procedure_Call_Statement
2618 Nkind (Name (Last_Stm)) = N_Identifier
2620 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
2622 -- Don't count exception junk
2625 ((Nkind (Last_Stm) = N_Goto_Statement
2626 or else Nkind (Last_Stm) = N_Label
2627 or else Nkind (Last_Stm) = N_Object_Declaration)
2628 and then Exception_Junk (Last_Stm))
2633 -- Here we have the "real" last statement
2635 Kind := Nkind (Last_Stm);
2637 -- Transfer of control, OK. Note that in the No_Return procedure
2638 -- case, we already diagnosed any explicit return statements, so
2639 -- we can treat them as OK in this context.
2641 if Is_Transfer (Last_Stm) then
2644 -- Check cases of explicit non-indirect procedure calls
2646 elsif Kind = N_Procedure_Call_Statement
2647 and then Is_Entity_Name (Name (Last_Stm))
2649 -- Check call to Raise_Exception procedure which is treated
2650 -- specially, as is a call to Reraise_Occurrence.
2652 -- We suppress the warning in these cases since it is likely that
2653 -- the programmer really does not expect to deal with the case
2654 -- of Null_Occurrence, and thus would find a warning about a
2655 -- missing return curious, and raising Program_Error does not
2656 -- seem such a bad behavior if this does occur.
2658 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
2660 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
2662 Raise_Exception_Call := True;
2664 -- For Raise_Exception call, test first argument, if it is
2665 -- an attribute reference for a 'Identity call, then we know
2666 -- that the call cannot possibly return.
2669 Arg : constant Node_Id :=
2670 Original_Node (First_Actual (Last_Stm));
2673 if Nkind (Arg) = N_Attribute_Reference
2674 and then Attribute_Name (Arg) = Name_Identity
2681 -- If statement, need to look inside if there is an else and check
2682 -- each constituent statement sequence for proper termination.
2684 elsif Kind = N_If_Statement
2685 and then Present (Else_Statements (Last_Stm))
2687 Check_Statement_Sequence (Then_Statements (Last_Stm));
2688 Check_Statement_Sequence (Else_Statements (Last_Stm));
2690 if Present (Elsif_Parts (Last_Stm)) then
2692 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
2695 while Present (Elsif_Part) loop
2696 Check_Statement_Sequence (Then_Statements (Elsif_Part));
2704 -- Case statement, check each case for proper termination
2706 elsif Kind = N_Case_Statement then
2711 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
2712 while Present (Case_Alt) loop
2713 Check_Statement_Sequence (Statements (Case_Alt));
2714 Next_Non_Pragma (Case_Alt);
2720 -- Block statement, check its handled sequence of statements
2722 elsif Kind = N_Block_Statement then
2728 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
2737 -- Loop statement. If there is an iteration scheme, we can definitely
2738 -- fall out of the loop. Similarly if there is an exit statement, we
2739 -- can fall out. In either case we need a following return.
2741 elsif Kind = N_Loop_Statement then
2742 if Present (Iteration_Scheme (Last_Stm))
2743 or else Has_Exit (Entity (Identifier (Last_Stm)))
2747 -- A loop with no exit statement or iteration scheme if either
2748 -- an inifite loop, or it has some other exit (raise/return).
2749 -- In either case, no warning is required.
2755 -- Timed entry call, check entry call and delay alternatives
2757 -- Note: in expanded code, the timed entry call has been converted
2758 -- to a set of expanded statements on which the check will work
2759 -- correctly in any case.
2761 elsif Kind = N_Timed_Entry_Call then
2763 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
2764 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
2767 -- If statement sequence of entry call alternative is missing,
2768 -- then we can definitely fall through, and we post the error
2769 -- message on the entry call alternative itself.
2771 if No (Statements (ECA)) then
2774 -- If statement sequence of delay alternative is missing, then
2775 -- we can definitely fall through, and we post the error
2776 -- message on the delay alternative itself.
2778 -- Note: if both ECA and DCA are missing the return, then we
2779 -- post only one message, should be enough to fix the bugs.
2780 -- If not we will get a message next time on the DCA when the
2783 elsif No (Statements (DCA)) then
2786 -- Else check both statement sequences
2789 Check_Statement_Sequence (Statements (ECA));
2790 Check_Statement_Sequence (Statements (DCA));
2795 -- Conditional entry call, check entry call and else part
2797 -- Note: in expanded code, the conditional entry call has been
2798 -- converted to a set of expanded statements on which the check
2799 -- will work correctly in any case.
2801 elsif Kind = N_Conditional_Entry_Call then
2803 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
2806 -- If statement sequence of entry call alternative is missing,
2807 -- then we can definitely fall through, and we post the error
2808 -- message on the entry call alternative itself.
2810 if No (Statements (ECA)) then
2813 -- Else check statement sequence and else part
2816 Check_Statement_Sequence (Statements (ECA));
2817 Check_Statement_Sequence (Else_Statements (Last_Stm));
2823 -- If we fall through, issue appropriate message
2827 if not Raise_Exception_Call then
2829 ("?RETURN statement missing following this statement!",
2832 ("\?Program_Error may be raised at run time",
2836 -- Note: we set Err even though we have not issued a warning
2837 -- because we still have a case of a missing return. This is
2838 -- an extremely marginal case, probably will never be noticed
2839 -- but we might as well get it right.
2845 ("implied return after this statement not allowed (No_Return)",
2848 end Check_Statement_Sequence;
2850 -- Start of processing for Check_Returns
2854 Check_Statement_Sequence (Statements (HSS));
2856 if Present (Exception_Handlers (HSS)) then
2857 Handler := First_Non_Pragma (Exception_Handlers (HSS));
2858 while Present (Handler) loop
2859 Check_Statement_Sequence (Statements (Handler));
2860 Next_Non_Pragma (Handler);
2865 ----------------------------
2866 -- Check_Subprogram_Order --
2867 ----------------------------
2869 procedure Check_Subprogram_Order (N : Node_Id) is
2871 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
2872 -- This is used to check if S1 > S2 in the sense required by this
2873 -- test, for example nameab < namec, but name2 < name10.
2875 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
2880 -- Remove trailing numeric parts
2883 while S1 (L1) in '0' .. '9' loop
2888 while S2 (L2) in '0' .. '9' loop
2892 -- If non-numeric parts non-equal, that's decisive
2894 if S1 (S1'First .. L1) < S2 (S2'First .. L2) then
2897 elsif S1 (S1'First .. L1) > S2 (S2'First .. L2) then
2900 -- If non-numeric parts equal, compare suffixed numeric parts. Note
2901 -- that a missing suffix is treated as numeric zero in this test.
2905 while L1 < S1'Last loop
2907 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
2911 while L2 < S2'Last loop
2913 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
2918 end Subprogram_Name_Greater;
2920 -- Start of processing for Check_Subprogram_Order
2923 -- Check body in alpha order if this is option
2926 and then Style_Check_Subprogram_Order
2927 and then Nkind (N) = N_Subprogram_Body
2928 and then Comes_From_Source (N)
2929 and then In_Extended_Main_Source_Unit (N)
2933 renames Scope_Stack.Table
2934 (Scope_Stack.Last).Last_Subprogram_Name;
2936 Body_Id : constant Entity_Id :=
2937 Defining_Entity (Specification (N));
2940 Get_Decoded_Name_String (Chars (Body_Id));
2943 if Subprogram_Name_Greater
2944 (LSN.all, Name_Buffer (1 .. Name_Len))
2946 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
2952 LSN := new String'(Name_Buffer (1 .. Name_Len));
2955 end Check_Subprogram_Order;
2957 ------------------------------
2958 -- Check_Subtype_Conformant --
2959 ------------------------------
2961 procedure Check_Subtype_Conformant
2962 (New_Id : Entity_Id;
2964 Err_Loc : Node_Id := Empty)
2970 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc);
2971 end Check_Subtype_Conformant;
2973 ---------------------------
2974 -- Check_Type_Conformant --
2975 ---------------------------
2977 procedure Check_Type_Conformant
2978 (New_Id : Entity_Id;
2980 Err_Loc : Node_Id := Empty)
2986 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
2987 end Check_Type_Conformant;
2989 ----------------------
2990 -- Conforming_Types --
2991 ----------------------
2993 function Conforming_Types
2996 Ctype : Conformance_Type;
2997 Get_Inst : Boolean := False) return Boolean
2999 Type_1 : Entity_Id := T1;
3000 Type_2 : Entity_Id := T2;
3001 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
3003 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean;
3004 -- If neither T1 nor T2 are generic actual types, or if they are
3005 -- in different scopes (e.g. parent and child instances), then verify
3006 -- that the base types are equal. Otherwise T1 and T2 must be
3007 -- on the same subtype chain. The whole purpose of this procedure
3008 -- is to prevent spurious ambiguities in an instantiation that may
3009 -- arise if two distinct generic types are instantiated with the
3012 ----------------------
3013 -- Base_Types_Match --
3014 ----------------------
3016 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean is
3021 elsif Base_Type (T1) = Base_Type (T2) then
3023 -- The following is too permissive. A more precise test must
3024 -- check that the generic actual is an ancestor subtype of the
3027 return not Is_Generic_Actual_Type (T1)
3028 or else not Is_Generic_Actual_Type (T2)
3029 or else Scope (T1) /= Scope (T2);
3031 -- In some cases a type imported through a limited_with clause,
3032 -- and its non-limited view are both visible, for example in an
3033 -- anonymous access_to_classwide type in a formal. Both entities
3034 -- designate the same type.
3036 elsif From_With_Type (T1)
3037 and then Ekind (T1) = E_Incomplete_Type
3038 and then T2 = Non_Limited_View (T1)
3045 end Base_Types_Match;
3048 -- The context is an instance association for a formal
3049 -- access-to-subprogram type; the formal parameter types
3050 -- require mapping because they may denote other formal
3051 -- parameters of the generic unit.
3054 Type_1 := Get_Instance_Of (T1);
3055 Type_2 := Get_Instance_Of (T2);
3058 -- First see if base types match
3060 if Base_Types_Match (Type_1, Type_2) then
3061 return Ctype <= Mode_Conformant
3062 or else Subtypes_Statically_Match (Type_1, Type_2);
3064 elsif Is_Incomplete_Or_Private_Type (Type_1)
3065 and then Present (Full_View (Type_1))
3066 and then Base_Types_Match (Full_View (Type_1), Type_2)
3068 return Ctype <= Mode_Conformant
3069 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
3071 elsif Ekind (Type_2) = E_Incomplete_Type
3072 and then Present (Full_View (Type_2))
3073 and then Base_Types_Match (Type_1, Full_View (Type_2))
3075 return Ctype <= Mode_Conformant
3076 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
3078 elsif Is_Private_Type (Type_2)
3079 and then In_Instance
3080 and then Present (Full_View (Type_2))
3081 and then Base_Types_Match (Type_1, Full_View (Type_2))
3083 return Ctype <= Mode_Conformant
3084 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
3087 -- Ada 0Y (AI-254): Detect anonymous access to subprogram types.
3089 Are_Anonymous_Access_To_Subprogram_Types :=
3091 -- Case 1: Anonymous access to subprogram types
3093 (Ekind (Type_1) = E_Anonymous_Access_Subprogram_Type
3094 and then Ekind (Type_2) = E_Anonymous_Access_Subprogram_Type)
3096 -- Case 2: Anonymous access to PROTECTED subprogram types. In this
3097 -- case the anonymous type_declaration has been replaced by an
3098 -- occurrence of an internal access to subprogram type declaration
3099 -- available through the Original_Access_Type attribute
3102 (Ekind (Type_1) = E_Access_Protected_Subprogram_Type
3103 and then Ekind (Type_2) = E_Access_Protected_Subprogram_Type
3104 and then not Comes_From_Source (Type_1)
3105 and then not Comes_From_Source (Type_2)
3106 and then Present (Original_Access_Type (Type_1))
3107 and then Present (Original_Access_Type (Type_2))
3108 and then Ekind (Original_Access_Type (Type_1)) =
3109 E_Anonymous_Access_Protected_Subprogram_Type
3110 and then Ekind (Original_Access_Type (Type_2)) =
3111 E_Anonymous_Access_Protected_Subprogram_Type);
3113 -- Test anonymous access type case. For this case, static subtype
3114 -- matching is required for mode conformance (RM 6.3.1(15))
3116 if (Ekind (Type_1) = E_Anonymous_Access_Type
3117 and then Ekind (Type_2) = E_Anonymous_Access_Type)
3118 or else Are_Anonymous_Access_To_Subprogram_Types -- Ada 0Y (AI-254)
3121 Desig_1 : Entity_Id;
3122 Desig_2 : Entity_Id;
3125 Desig_1 := Directly_Designated_Type (Type_1);
3127 -- An access parameter can designate an incomplete type
3129 if Ekind (Desig_1) = E_Incomplete_Type
3130 and then Present (Full_View (Desig_1))
3132 Desig_1 := Full_View (Desig_1);
3135 Desig_2 := Directly_Designated_Type (Type_2);
3137 if Ekind (Desig_2) = E_Incomplete_Type
3138 and then Present (Full_View (Desig_2))
3140 Desig_2 := Full_View (Desig_2);
3143 -- The context is an instance association for a formal
3144 -- access-to-subprogram type; formal access parameter
3145 -- designated types require mapping because they may
3146 -- denote other formal parameters of the generic unit.
3149 Desig_1 := Get_Instance_Of (Desig_1);
3150 Desig_2 := Get_Instance_Of (Desig_2);
3153 -- It is possible for a Class_Wide_Type to be introduced for
3154 -- an incomplete type, in which case there is a separate class_
3155 -- wide type for the full view. The types conform if their
3156 -- Etypes conform, i.e. one may be the full view of the other.
3157 -- This can only happen in the context of an access parameter,
3158 -- other uses of an incomplete Class_Wide_Type are illegal.
3160 if Is_Class_Wide_Type (Desig_1)
3161 and then Is_Class_Wide_Type (Desig_2)
3165 (Etype (Base_Type (Desig_1)),
3166 Etype (Base_Type (Desig_2)), Ctype);
3168 elsif Are_Anonymous_Access_To_Subprogram_Types then
3169 return Ctype = Type_Conformant
3171 Subtypes_Statically_Match (Desig_1, Desig_2);
3174 return Base_Type (Desig_1) = Base_Type (Desig_2)
3175 and then (Ctype = Type_Conformant
3177 Subtypes_Statically_Match (Desig_1, Desig_2));
3181 -- Otherwise definitely no match
3187 end Conforming_Types;
3189 --------------------------
3190 -- Create_Extra_Formals --
3191 --------------------------
3193 procedure Create_Extra_Formals (E : Entity_Id) is
3195 Last_Extra : Entity_Id;
3196 Formal_Type : Entity_Id;
3197 P_Formal : Entity_Id := Empty;
3199 function Add_Extra_Formal (Typ : Entity_Id) return Entity_Id;
3200 -- Add an extra formal, associated with the current Formal. The
3201 -- extra formal is added to the list of extra formals, and also
3202 -- returned as the result. These formals are always of mode IN.
3204 ----------------------
3205 -- Add_Extra_Formal --
3206 ----------------------
3208 function Add_Extra_Formal (Typ : Entity_Id) return Entity_Id is
3209 EF : constant Entity_Id :=
3210 Make_Defining_Identifier (Sloc (Formal),
3211 Chars => New_External_Name (Chars (Formal), 'F'));
3214 -- We never generate extra formals if expansion is not active
3215 -- because we don't need them unless we are generating code.
3217 if not Expander_Active then
3221 -- A little optimization. Never generate an extra formal for
3222 -- the _init operand of an initialization procedure, since it
3223 -- could never be used.
3225 if Chars (Formal) = Name_uInit then
3229 Set_Ekind (EF, E_In_Parameter);
3230 Set_Actual_Subtype (EF, Typ);
3231 Set_Etype (EF, Typ);
3232 Set_Scope (EF, Scope (Formal));
3233 Set_Mechanism (EF, Default_Mechanism);
3234 Set_Formal_Validity (EF);
3236 Set_Extra_Formal (Last_Extra, EF);
3239 end Add_Extra_Formal;
3241 -- Start of processing for Create_Extra_Formals
3244 -- If this is a derived subprogram then the subtypes of the
3245 -- parent subprogram's formal parameters will be used to
3246 -- to determine the need for extra formals.
3248 if Is_Overloadable (E) and then Present (Alias (E)) then
3249 P_Formal := First_Formal (Alias (E));
3252 Last_Extra := Empty;
3253 Formal := First_Formal (E);
3254 while Present (Formal) loop
3255 Last_Extra := Formal;
3256 Next_Formal (Formal);
3259 -- If Extra_formals where already created, don't do it again
3260 -- This situation may arise for subprogram types created as part
3261 -- of dispatching calls (see Expand_Dispatch_Call)
3263 if Present (Last_Extra) and then
3264 Present (Extra_Formal (Last_Extra))
3269 Formal := First_Formal (E);
3271 while Present (Formal) loop
3273 -- Create extra formal for supporting the attribute 'Constrained.
3274 -- The case of a private type view without discriminants also
3275 -- requires the extra formal if the underlying type has defaulted
3278 if Ekind (Formal) /= E_In_Parameter then
3279 if Present (P_Formal) then
3280 Formal_Type := Etype (P_Formal);
3282 Formal_Type := Etype (Formal);
3285 if not Has_Discriminants (Formal_Type)
3286 and then Ekind (Formal_Type) in Private_Kind
3287 and then Present (Underlying_Type (Formal_Type))
3289 Formal_Type := Underlying_Type (Formal_Type);
3292 if Has_Discriminants (Formal_Type)
3294 ((not Is_Constrained (Formal_Type)
3295 and then not Is_Indefinite_Subtype (Formal_Type))
3296 or else Present (Extra_Formal (Formal)))
3298 Set_Extra_Constrained
3299 (Formal, Add_Extra_Formal (Standard_Boolean));
3303 -- Create extra formal for supporting accessibility checking
3305 -- This is suppressed if we specifically suppress accessibility
3306 -- checks at the pacage level for either the subprogram, or the
3307 -- package in which it resides. However, we do not suppress it
3308 -- simply if the scope has accessibility checks suppressed, since
3309 -- this could cause trouble when clients are compiled with a
3310 -- different suppression setting. The explicit checks at the
3311 -- package level are safe from this point of view.
3313 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type
3315 (Explicit_Suppress (E, Accessibility_Check)
3317 Explicit_Suppress (Scope (E), Accessibility_Check))
3319 (not Present (P_Formal)
3320 or else Present (Extra_Accessibility (P_Formal)))
3322 -- Temporary kludge: for now we avoid creating the extra
3323 -- formal for access parameters of protected operations
3324 -- because of problem with the case of internal protected
3327 if Nkind (Parent (Parent (Parent (E)))) /= N_Protected_Definition
3328 and then Nkind (Parent (Parent (Parent (E)))) /= N_Protected_Body
3330 Set_Extra_Accessibility
3331 (Formal, Add_Extra_Formal (Standard_Natural));
3335 if Present (P_Formal) then
3336 Next_Formal (P_Formal);
3339 Next_Formal (Formal);
3341 end Create_Extra_Formals;
3343 -----------------------------
3344 -- Enter_Overloaded_Entity --
3345 -----------------------------
3347 procedure Enter_Overloaded_Entity (S : Entity_Id) is
3348 E : Entity_Id := Current_Entity_In_Scope (S);
3349 C_E : Entity_Id := Current_Entity (S);
3353 Set_Has_Homonym (E);
3354 Set_Has_Homonym (S);
3357 Set_Is_Immediately_Visible (S);
3358 Set_Scope (S, Current_Scope);
3360 -- Chain new entity if front of homonym in current scope, so that
3361 -- homonyms are contiguous.
3366 while Homonym (C_E) /= E loop
3367 C_E := Homonym (C_E);
3370 Set_Homonym (C_E, S);
3374 Set_Current_Entity (S);
3379 Append_Entity (S, Current_Scope);
3380 Set_Public_Status (S);
3382 if Debug_Flag_E then
3383 Write_Str ("New overloaded entity chain: ");
3384 Write_Name (Chars (S));
3387 while Present (E) loop
3388 Write_Str (" "); Write_Int (Int (E));
3395 -- Generate warning for hiding
3398 and then Comes_From_Source (S)
3399 and then In_Extended_Main_Source_Unit (S)
3406 -- Warn unless genuine overloading
3408 if (not Is_Overloadable (E))
3409 or else Subtype_Conformant (E, S)
3411 Error_Msg_Sloc := Sloc (E);
3412 Error_Msg_N ("declaration of & hides one#?", S);
3416 end Enter_Overloaded_Entity;
3418 -----------------------------
3419 -- Find_Corresponding_Spec --
3420 -----------------------------
3422 function Find_Corresponding_Spec (N : Node_Id) return Entity_Id is
3423 Spec : constant Node_Id := Specification (N);
3424 Designator : constant Entity_Id := Defining_Entity (Spec);
3429 E := Current_Entity (Designator);
3431 while Present (E) loop
3433 -- We are looking for a matching spec. It must have the same scope,
3434 -- and the same name, and either be type conformant, or be the case
3435 -- of a library procedure spec and its body (which belong to one
3436 -- another regardless of whether they are type conformant or not).
3438 if Scope (E) = Current_Scope then
3439 if Current_Scope = Standard_Standard
3440 or else (Ekind (E) = Ekind (Designator)
3441 and then Type_Conformant (E, Designator))
3443 -- Within an instantiation, we know that spec and body are
3444 -- subtype conformant, because they were subtype conformant
3445 -- in the generic. We choose the subtype-conformant entity
3446 -- here as well, to resolve spurious ambiguities in the
3447 -- instance that were not present in the generic (i.e. when
3448 -- two different types are given the same actual). If we are
3449 -- looking for a spec to match a body, full conformance is
3453 Set_Convention (Designator, Convention (E));
3455 if Nkind (N) = N_Subprogram_Body
3456 and then Present (Homonym (E))
3457 and then not Fully_Conformant (E, Designator)
3461 elsif not Subtype_Conformant (E, Designator) then
3466 if not Has_Completion (E) then
3468 if Nkind (N) /= N_Subprogram_Body_Stub then
3469 Set_Corresponding_Spec (N, E);
3472 Set_Has_Completion (E);
3475 elsif Nkind (Parent (N)) = N_Subunit then
3477 -- If this is the proper body of a subunit, the completion
3478 -- flag is set when analyzing the stub.
3482 -- If body already exists, this is an error unless the
3483 -- previous declaration is the implicit declaration of
3484 -- a derived subprogram, or this is a spurious overloading
3487 elsif No (Alias (E))
3488 and then not Is_Intrinsic_Subprogram (E)
3489 and then not In_Instance
3491 Error_Msg_Sloc := Sloc (E);
3492 if Is_Imported (E) then
3494 ("body not allowed for imported subprogram & declared#",
3497 Error_Msg_NE ("duplicate body for & declared#", N, E);
3501 elsif Is_Child_Unit (E)
3503 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
3505 Nkind (Parent (Unit_Declaration_Node (Designator)))
3506 = N_Compilation_Unit
3509 -- Child units cannot be overloaded, so a conformance mismatch
3510 -- between body and a previous spec is an error.
3513 ("body of child unit does not match previous declaration", N);
3521 -- On exit, we know that no previous declaration of subprogram exists
3524 end Find_Corresponding_Spec;
3526 ----------------------
3527 -- Fully_Conformant --
3528 ----------------------
3530 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
3534 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
3536 end Fully_Conformant;
3538 ----------------------------------
3539 -- Fully_Conformant_Expressions --
3540 ----------------------------------
3542 function Fully_Conformant_Expressions
3543 (Given_E1 : Node_Id;
3544 Given_E2 : Node_Id) return Boolean
3546 E1 : constant Node_Id := Original_Node (Given_E1);
3547 E2 : constant Node_Id := Original_Node (Given_E2);
3548 -- We always test conformance on original nodes, since it is possible
3549 -- for analysis and/or expansion to make things look as though they
3550 -- conform when they do not, e.g. by converting 1+2 into 3.
3552 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
3553 renames Fully_Conformant_Expressions;
3555 function FCL (L1, L2 : List_Id) return Boolean;
3556 -- Compare elements of two lists for conformance. Elements have to
3557 -- be conformant, and actuals inserted as default parameters do not
3558 -- match explicit actuals with the same value.
3560 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
3561 -- Compare an operator node with a function call.
3567 function FCL (L1, L2 : List_Id) return Boolean is
3571 if L1 = No_List then
3577 if L2 = No_List then
3583 -- Compare two lists, skipping rewrite insertions (we want to
3584 -- compare the original trees, not the expanded versions!)
3587 if Is_Rewrite_Insertion (N1) then
3589 elsif Is_Rewrite_Insertion (N2) then
3595 elsif not FCE (N1, N2) then
3608 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
3609 Actuals : constant List_Id := Parameter_Associations (Call_Node);
3614 or else Entity (Op_Node) /= Entity (Name (Call_Node))
3619 Act := First (Actuals);
3621 if Nkind (Op_Node) in N_Binary_Op then
3623 if not FCE (Left_Opnd (Op_Node), Act) then
3630 return Present (Act)
3631 and then FCE (Right_Opnd (Op_Node), Act)
3632 and then No (Next (Act));
3636 -- Start of processing for Fully_Conformant_Expressions
3639 -- Non-conformant if paren count does not match. Note: if some idiot
3640 -- complains that we don't do this right for more than 3 levels of
3641 -- parentheses, they will be treated with the respect they deserve :-)
3643 if Paren_Count (E1) /= Paren_Count (E2) then
3646 -- If same entities are referenced, then they are conformant
3647 -- even if they have different forms (RM 8.3.1(19-20)).
3649 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
3650 if Present (Entity (E1)) then
3651 return Entity (E1) = Entity (E2)
3652 or else (Chars (Entity (E1)) = Chars (Entity (E2))
3653 and then Ekind (Entity (E1)) = E_Discriminant
3654 and then Ekind (Entity (E2)) = E_In_Parameter);
3656 elsif Nkind (E1) = N_Expanded_Name
3657 and then Nkind (E2) = N_Expanded_Name
3658 and then Nkind (Selector_Name (E1)) = N_Character_Literal
3659 and then Nkind (Selector_Name (E2)) = N_Character_Literal
3661 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
3664 -- Identifiers in component associations don't always have
3665 -- entities, but their names must conform.
3667 return Nkind (E1) = N_Identifier
3668 and then Nkind (E2) = N_Identifier
3669 and then Chars (E1) = Chars (E2);
3672 elsif Nkind (E1) = N_Character_Literal
3673 and then Nkind (E2) = N_Expanded_Name
3675 return Nkind (Selector_Name (E2)) = N_Character_Literal
3676 and then Chars (E1) = Chars (Selector_Name (E2));
3678 elsif Nkind (E2) = N_Character_Literal
3679 and then Nkind (E1) = N_Expanded_Name
3681 return Nkind (Selector_Name (E1)) = N_Character_Literal
3682 and then Chars (E2) = Chars (Selector_Name (E1));
3684 elsif Nkind (E1) in N_Op
3685 and then Nkind (E2) = N_Function_Call
3687 return FCO (E1, E2);
3689 elsif Nkind (E2) in N_Op
3690 and then Nkind (E1) = N_Function_Call
3692 return FCO (E2, E1);
3694 -- Otherwise we must have the same syntactic entity
3696 elsif Nkind (E1) /= Nkind (E2) then
3699 -- At this point, we specialize by node type
3706 FCL (Expressions (E1), Expressions (E2))
3707 and then FCL (Component_Associations (E1),
3708 Component_Associations (E2));
3711 if Nkind (Expression (E1)) = N_Qualified_Expression
3713 Nkind (Expression (E2)) = N_Qualified_Expression
3715 return FCE (Expression (E1), Expression (E2));
3717 -- Check that the subtype marks and any constraints
3722 Indic1 : constant Node_Id := Expression (E1);
3723 Indic2 : constant Node_Id := Expression (E2);
3728 if Nkind (Indic1) /= N_Subtype_Indication then
3730 Nkind (Indic2) /= N_Subtype_Indication
3731 and then Entity (Indic1) = Entity (Indic2);
3733 elsif Nkind (Indic2) /= N_Subtype_Indication then
3735 Nkind (Indic1) /= N_Subtype_Indication
3736 and then Entity (Indic1) = Entity (Indic2);
3739 if Entity (Subtype_Mark (Indic1)) /=
3740 Entity (Subtype_Mark (Indic2))
3745 Elt1 := First (Constraints (Constraint (Indic1)));
3746 Elt2 := First (Constraints (Constraint (Indic2)));
3748 while Present (Elt1) and then Present (Elt2) loop
3749 if not FCE (Elt1, Elt2) then
3762 when N_Attribute_Reference =>
3764 Attribute_Name (E1) = Attribute_Name (E2)
3765 and then FCL (Expressions (E1), Expressions (E2));
3769 Entity (E1) = Entity (E2)
3770 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
3771 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
3773 when N_And_Then | N_Or_Else | N_In | N_Not_In =>
3775 FCE (Left_Opnd (E1), Left_Opnd (E2))
3777 FCE (Right_Opnd (E1), Right_Opnd (E2));
3779 when N_Character_Literal =>
3781 Char_Literal_Value (E1) = Char_Literal_Value (E2);
3783 when N_Component_Association =>
3785 FCL (Choices (E1), Choices (E2))
3786 and then FCE (Expression (E1), Expression (E2));
3788 when N_Conditional_Expression =>
3790 FCL (Expressions (E1), Expressions (E2));
3792 when N_Explicit_Dereference =>
3794 FCE (Prefix (E1), Prefix (E2));
3796 when N_Extension_Aggregate =>
3798 FCL (Expressions (E1), Expressions (E2))
3799 and then Null_Record_Present (E1) =
3800 Null_Record_Present (E2)
3801 and then FCL (Component_Associations (E1),
3802 Component_Associations (E2));
3804 when N_Function_Call =>
3806 FCE (Name (E1), Name (E2))
3807 and then FCL (Parameter_Associations (E1),
3808 Parameter_Associations (E2));
3810 when N_Indexed_Component =>
3812 FCE (Prefix (E1), Prefix (E2))
3813 and then FCL (Expressions (E1), Expressions (E2));
3815 when N_Integer_Literal =>
3816 return (Intval (E1) = Intval (E2));
3821 when N_Operator_Symbol =>
3823 Chars (E1) = Chars (E2);
3825 when N_Others_Choice =>
3828 when N_Parameter_Association =>
3830 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
3831 and then FCE (Explicit_Actual_Parameter (E1),
3832 Explicit_Actual_Parameter (E2));
3834 when N_Qualified_Expression =>
3836 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
3837 and then FCE (Expression (E1), Expression (E2));
3841 FCE (Low_Bound (E1), Low_Bound (E2))
3842 and then FCE (High_Bound (E1), High_Bound (E2));
3844 when N_Real_Literal =>
3845 return (Realval (E1) = Realval (E2));
3847 when N_Selected_Component =>
3849 FCE (Prefix (E1), Prefix (E2))
3850 and then FCE (Selector_Name (E1), Selector_Name (E2));
3854 FCE (Prefix (E1), Prefix (E2))
3855 and then FCE (Discrete_Range (E1), Discrete_Range (E2));
3857 when N_String_Literal =>
3859 S1 : constant String_Id := Strval (E1);
3860 S2 : constant String_Id := Strval (E2);
3861 L1 : constant Nat := String_Length (S1);
3862 L2 : constant Nat := String_Length (S2);
3869 for J in 1 .. L1 loop
3870 if Get_String_Char (S1, J) /=
3871 Get_String_Char (S2, J)
3881 when N_Type_Conversion =>
3883 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
3884 and then FCE (Expression (E1), Expression (E2));
3888 Entity (E1) = Entity (E2)
3889 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
3891 when N_Unchecked_Type_Conversion =>
3893 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
3894 and then FCE (Expression (E1), Expression (E2));
3896 -- All other node types cannot appear in this context. Strictly
3897 -- we should raise a fatal internal error. Instead we just ignore
3898 -- the nodes. This means that if anyone makes a mistake in the
3899 -- expander and mucks an expression tree irretrievably, the
3900 -- result will be a failure to detect a (probably very obscure)
3901 -- case of non-conformance, which is better than bombing on some
3902 -- case where two expressions do in fact conform.
3909 end Fully_Conformant_Expressions;
3911 ----------------------------------------
3912 -- Fully_Conformant_Discrete_Subtypes --
3913 ----------------------------------------
3915 function Fully_Conformant_Discrete_Subtypes
3916 (Given_S1 : Node_Id;
3917 Given_S2 : Node_Id) return Boolean
3919 S1 : constant Node_Id := Original_Node (Given_S1);
3920 S2 : constant Node_Id := Original_Node (Given_S2);
3922 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
3923 -- Special-case for a bound given by a discriminant, which in the
3924 -- body is replaced with the discriminal of the enclosing type.
3926 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
3927 -- Check both bounds.
3929 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
3931 if Is_Entity_Name (B1)
3932 and then Is_Entity_Name (B2)
3933 and then Ekind (Entity (B1)) = E_Discriminant
3935 return Chars (B1) = Chars (B2);
3938 return Fully_Conformant_Expressions (B1, B2);
3940 end Conforming_Bounds;
3942 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
3945 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
3947 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
3948 end Conforming_Ranges;
3950 -- Start of processing for Fully_Conformant_Discrete_Subtypes
3953 if Nkind (S1) /= Nkind (S2) then
3956 elsif Is_Entity_Name (S1) then
3957 return Entity (S1) = Entity (S2);
3959 elsif Nkind (S1) = N_Range then
3960 return Conforming_Ranges (S1, S2);
3962 elsif Nkind (S1) = N_Subtype_Indication then
3964 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
3967 (Range_Expression (Constraint (S1)),
3968 Range_Expression (Constraint (S2)));
3972 end Fully_Conformant_Discrete_Subtypes;
3974 --------------------
3975 -- Install_Entity --
3976 --------------------
3978 procedure Install_Entity (E : Entity_Id) is
3979 Prev : constant Entity_Id := Current_Entity (E);
3982 Set_Is_Immediately_Visible (E);
3983 Set_Current_Entity (E);
3984 Set_Homonym (E, Prev);
3987 ---------------------
3988 -- Install_Formals --
3989 ---------------------
3991 procedure Install_Formals (Id : Entity_Id) is
3995 F := First_Formal (Id);
3997 while Present (F) loop
4001 end Install_Formals;
4003 ---------------------------------
4004 -- Is_Non_Overriding_Operation --
4005 ---------------------------------
4007 function Is_Non_Overriding_Operation
4008 (Prev_E : Entity_Id;
4009 New_E : Entity_Id) return Boolean
4013 G_Typ : Entity_Id := Empty;
4015 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
4016 -- If F_Type is a derived type associated with a generic actual
4017 -- subtype, then return its Generic_Parent_Type attribute, else
4020 function Types_Correspond
4021 (P_Type : Entity_Id;
4022 N_Type : Entity_Id) return Boolean;
4023 -- Returns true if and only if the types (or designated types
4024 -- in the case of anonymous access types) are the same or N_Type
4025 -- is derived directly or indirectly from P_Type.
4027 -----------------------------
4028 -- Get_Generic_Parent_Type --
4029 -----------------------------
4031 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
4036 if Is_Derived_Type (F_Typ)
4037 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
4039 -- The tree must be traversed to determine the parent
4040 -- subtype in the generic unit, which unfortunately isn't
4041 -- always available via semantic attributes. ???
4042 -- (Note: The use of Original_Node is needed for cases
4043 -- where a full derived type has been rewritten.)
4045 Indic := Subtype_Indication
4046 (Type_Definition (Original_Node (Parent (F_Typ))));
4048 if Nkind (Indic) = N_Subtype_Indication then
4049 G_Typ := Entity (Subtype_Mark (Indic));
4051 G_Typ := Entity (Indic);
4054 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
4055 and then Present (Generic_Parent_Type (Parent (G_Typ)))
4057 return Generic_Parent_Type (Parent (G_Typ));
4062 end Get_Generic_Parent_Type;
4064 ----------------------
4065 -- Types_Correspond --
4066 ----------------------
4068 function Types_Correspond
4069 (P_Type : Entity_Id;
4070 N_Type : Entity_Id) return Boolean
4072 Prev_Type : Entity_Id := Base_Type (P_Type);
4073 New_Type : Entity_Id := Base_Type (N_Type);
4076 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
4077 Prev_Type := Designated_Type (Prev_Type);
4080 if Ekind (New_Type) = E_Anonymous_Access_Type then
4081 New_Type := Designated_Type (New_Type);
4084 if Prev_Type = New_Type then
4087 elsif not Is_Class_Wide_Type (New_Type) then
4088 while Etype (New_Type) /= New_Type loop
4089 New_Type := Etype (New_Type);
4090 if New_Type = Prev_Type then
4096 end Types_Correspond;
4098 -- Start of processing for Is_Non_Overriding_Operation
4101 -- In the case where both operations are implicit derived
4102 -- subprograms then neither overrides the other. This can
4103 -- only occur in certain obscure cases (e.g., derivation
4104 -- from homographs created in a generic instantiation).
4106 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
4109 elsif Ekind (Current_Scope) = E_Package
4110 and then Is_Generic_Instance (Current_Scope)
4111 and then In_Private_Part (Current_Scope)
4112 and then Comes_From_Source (New_E)
4114 -- We examine the formals and result subtype of the inherited
4115 -- operation, to determine whether their type is derived from
4116 -- (the instance of) a generic type.
4118 Formal := First_Formal (Prev_E);
4120 while Present (Formal) loop
4121 F_Typ := Base_Type (Etype (Formal));
4123 if Ekind (F_Typ) = E_Anonymous_Access_Type then
4124 F_Typ := Designated_Type (F_Typ);
4127 G_Typ := Get_Generic_Parent_Type (F_Typ);
4129 Next_Formal (Formal);
4132 if not Present (G_Typ) and then Ekind (Prev_E) = E_Function then
4133 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
4140 -- If the generic type is a private type, then the original
4141 -- operation was not overriding in the generic, because there was
4142 -- no primitive operation to override.
4144 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
4145 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
4146 N_Formal_Private_Type_Definition
4150 -- The generic parent type is the ancestor of a formal derived
4151 -- type declaration. We need to check whether it has a primitive
4152 -- operation that should be overridden by New_E in the generic.
4156 P_Formal : Entity_Id;
4157 N_Formal : Entity_Id;
4161 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
4164 while Present (Prim_Elt) loop
4165 P_Prim := Node (Prim_Elt);
4167 if Chars (P_Prim) = Chars (New_E)
4168 and then Ekind (P_Prim) = Ekind (New_E)
4170 P_Formal := First_Formal (P_Prim);
4171 N_Formal := First_Formal (New_E);
4172 while Present (P_Formal) and then Present (N_Formal) loop
4173 P_Typ := Etype (P_Formal);
4174 N_Typ := Etype (N_Formal);
4176 if not Types_Correspond (P_Typ, N_Typ) then
4180 Next_Entity (P_Formal);
4181 Next_Entity (N_Formal);
4184 -- Found a matching primitive operation belonging to
4185 -- the formal ancestor type, so the new subprogram
4188 if not Present (P_Formal)
4189 and then not Present (N_Formal)
4190 and then (Ekind (New_E) /= E_Function
4193 (Etype (P_Prim), Etype (New_E)))
4199 Next_Elmt (Prim_Elt);
4202 -- If no match found, then the new subprogram does
4203 -- not override in the generic (nor in the instance).
4211 end Is_Non_Overriding_Operation;
4213 ------------------------------
4214 -- Make_Inequality_Operator --
4215 ------------------------------
4217 -- S is the defining identifier of an equality operator. We build a
4218 -- subprogram declaration with the right signature. This operation is
4219 -- intrinsic, because it is always expanded as the negation of the
4220 -- call to the equality function.
4222 procedure Make_Inequality_Operator (S : Entity_Id) is
4223 Loc : constant Source_Ptr := Sloc (S);
4226 Op_Name : Entity_Id;
4232 -- Check that equality was properly defined.
4234 if No (Next_Formal (First_Formal (S))) then
4238 A := Make_Defining_Identifier (Loc, Chars (First_Formal (S)));
4239 B := Make_Defining_Identifier (Loc,
4240 Chars (Next_Formal (First_Formal (S))));
4242 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
4244 Formals := New_List (
4245 Make_Parameter_Specification (Loc,
4246 Defining_Identifier => A,
4248 New_Reference_To (Etype (First_Formal (S)), Loc)),
4250 Make_Parameter_Specification (Loc,
4251 Defining_Identifier => B,
4253 New_Reference_To (Etype (Next_Formal (First_Formal (S))), Loc)));
4256 Make_Subprogram_Declaration (Loc,
4258 Make_Function_Specification (Loc,
4259 Defining_Unit_Name => Op_Name,
4260 Parameter_Specifications => Formals,
4261 Subtype_Mark => New_Reference_To (Standard_Boolean, Loc)));
4263 -- Insert inequality right after equality if it is explicit or after
4264 -- the derived type when implicit. These entities are created only
4265 -- for visibility purposes, and eventually replaced in the course of
4266 -- expansion, so they do not need to be attached to the tree and seen
4267 -- by the back-end. Keeping them internal also avoids spurious freezing
4268 -- problems. The parent field is set simply to make analysis safe.
4270 if No (Alias (S)) then
4271 Set_Parent (Decl, Parent (Unit_Declaration_Node (S)));
4273 Set_Parent (Decl, Parent (Parent (Etype (First_Formal (S)))));
4276 Mark_Rewrite_Insertion (Decl);
4277 Set_Is_Intrinsic_Subprogram (Op_Name);
4279 Set_Has_Completion (Op_Name);
4280 Set_Corresponding_Equality (Op_Name, S);
4281 Set_Is_Abstract (Op_Name, Is_Abstract (S));
4283 end Make_Inequality_Operator;
4285 ----------------------
4286 -- May_Need_Actuals --
4287 ----------------------
4289 procedure May_Need_Actuals (Fun : Entity_Id) is
4294 F := First_Formal (Fun);
4297 while Present (F) loop
4298 if No (Default_Value (F)) then
4306 Set_Needs_No_Actuals (Fun, B);
4307 end May_Need_Actuals;
4309 ---------------------
4310 -- Mode_Conformant --
4311 ---------------------
4313 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
4317 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
4319 end Mode_Conformant;
4321 ---------------------------
4322 -- New_Overloaded_Entity --
4323 ---------------------------
4325 procedure New_Overloaded_Entity
4327 Derived_Type : Entity_Id := Empty)
4330 -- Entity that S overrides
4332 Prev_Vis : Entity_Id := Empty;
4333 -- Needs comment ???
4335 function Is_Private_Declaration (E : Entity_Id) return Boolean;
4336 -- Check that E is declared in the private part of the current package,
4337 -- or in the package body, where it may hide a previous declaration.
4338 -- We can't use In_Private_Part by itself because this flag is also
4339 -- set when freezing entities, so we must examine the place of the
4340 -- declaration in the tree, and recognize wrapper packages as well.
4342 procedure Maybe_Primitive_Operation (Overriding : Boolean := False);
4343 -- If the subprogram being analyzed is a primitive operation of
4344 -- the type of one of its formals, set the corresponding flag.
4346 ----------------------------
4347 -- Is_Private_Declaration --
4348 ----------------------------
4350 function Is_Private_Declaration (E : Entity_Id) return Boolean is
4351 Priv_Decls : List_Id;
4352 Decl : constant Node_Id := Unit_Declaration_Node (E);
4355 if Is_Package (Current_Scope)
4356 and then In_Private_Part (Current_Scope)
4359 Private_Declarations (
4360 Specification (Unit_Declaration_Node (Current_Scope)));
4362 return In_Package_Body (Current_Scope)
4363 or else List_Containing (Decl) = Priv_Decls
4364 or else (Nkind (Parent (Decl)) = N_Package_Specification
4365 and then not Is_Compilation_Unit (
4366 Defining_Entity (Parent (Decl)))
4367 and then List_Containing (Parent (Parent (Decl)))
4372 end Is_Private_Declaration;
4374 -------------------------------
4375 -- Maybe_Primitive_Operation --
4376 -------------------------------
4378 procedure Maybe_Primitive_Operation (Overriding : Boolean := False) is
4383 function Visible_Part_Type (T : Entity_Id) return Boolean;
4384 -- Returns true if T is declared in the visible part of
4385 -- the current package scope; otherwise returns false.
4386 -- Assumes that T is declared in a package.
4388 procedure Check_Private_Overriding (T : Entity_Id);
4389 -- Checks that if a primitive abstract subprogram of a visible
4390 -- abstract type is declared in a private part, then it must
4391 -- override an abstract subprogram declared in the visible part.
4392 -- Also checks that if a primitive function with a controlling
4393 -- result is declared in a private part, then it must override
4394 -- a function declared in the visible part.
4396 ------------------------------
4397 -- Check_Private_Overriding --
4398 ------------------------------
4400 procedure Check_Private_Overriding (T : Entity_Id) is
4402 if Ekind (Current_Scope) = E_Package
4403 and then In_Private_Part (Current_Scope)
4404 and then Visible_Part_Type (T)
4405 and then not In_Instance
4408 and then Is_Abstract (S)
4409 and then (not Overriding or else not Is_Abstract (E))
4411 Error_Msg_N ("abstract subprograms must be visible "
4412 & "('R'M 3.9.3(10))!", S);
4414 elsif Ekind (S) = E_Function
4415 and then Is_Tagged_Type (T)
4416 and then T = Base_Type (Etype (S))
4417 and then not Overriding
4420 ("private function with tagged result must"
4421 & " override visible-part function", S);
4423 ("\move subprogram to the visible part"
4424 & " ('R'M 3.9.3(10))", S);
4427 end Check_Private_Overriding;
4429 -----------------------
4430 -- Visible_Part_Type --
4431 -----------------------
4433 function Visible_Part_Type (T : Entity_Id) return Boolean is
4434 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
4438 -- If the entity is a private type, then it must be
4439 -- declared in a visible part.
4441 if Ekind (T) in Private_Kind then
4445 -- Otherwise, we traverse the visible part looking for its
4446 -- corresponding declaration. We cannot use the declaration
4447 -- node directly because in the private part the entity of a
4448 -- private type is the one in the full view, which does not
4449 -- indicate that it is the completion of something visible.
4451 N := First (Visible_Declarations (Specification (P)));
4452 while Present (N) loop
4453 if Nkind (N) = N_Full_Type_Declaration
4454 and then Present (Defining_Identifier (N))
4455 and then T = Defining_Identifier (N)
4459 elsif (Nkind (N) = N_Private_Type_Declaration
4461 Nkind (N) = N_Private_Extension_Declaration)
4462 and then Present (Defining_Identifier (N))
4463 and then T = Full_View (Defining_Identifier (N))
4472 end Visible_Part_Type;
4474 -- Start of processing for Maybe_Primitive_Operation
4477 if not Comes_From_Source (S) then
4480 elsif (Ekind (Current_Scope) = E_Package
4481 and then not In_Package_Body (Current_Scope))
4484 -- For function, check return type
4486 if Ekind (S) = E_Function then
4487 B_Typ := Base_Type (Etype (S));
4489 if Scope (B_Typ) = Current_Scope then
4490 Set_Has_Primitive_Operations (B_Typ);
4491 Check_Private_Overriding (B_Typ);
4495 -- For all subprograms, check formals
4497 Formal := First_Formal (S);
4498 while Present (Formal) loop
4499 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
4500 F_Typ := Designated_Type (Etype (Formal));
4502 F_Typ := Etype (Formal);
4505 B_Typ := Base_Type (F_Typ);
4507 if Scope (B_Typ) = Current_Scope then
4508 Set_Has_Primitive_Operations (B_Typ);
4509 Check_Private_Overriding (B_Typ);
4512 Next_Formal (Formal);
4515 end Maybe_Primitive_Operation;
4517 -- Start of processing for New_Overloaded_Entity
4520 -- We need to look for an entity that S may override. This must be a
4521 -- homonym in the current scope, so we look for the first homonym of
4522 -- S in the current scope as the starting point for the search.
4524 E := Current_Entity_In_Scope (S);
4526 -- If there is no homonym then this is definitely not overriding
4529 Enter_Overloaded_Entity (S);
4530 Check_Dispatching_Operation (S, Empty);
4531 Maybe_Primitive_Operation;
4533 -- If there is a homonym that is not overloadable, then we have an
4534 -- error, except for the special cases checked explicitly below.
4536 elsif not Is_Overloadable (E) then
4538 -- Check for spurious conflict produced by a subprogram that has the
4539 -- same name as that of the enclosing generic package. The conflict
4540 -- occurs within an instance, between the subprogram and the renaming
4541 -- declaration for the package. After the subprogram, the package
4542 -- renaming declaration becomes hidden.
4544 if Ekind (E) = E_Package
4545 and then Present (Renamed_Object (E))
4546 and then Renamed_Object (E) = Current_Scope
4547 and then Nkind (Parent (Renamed_Object (E))) =
4548 N_Package_Specification
4549 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
4552 Set_Is_Immediately_Visible (E, False);
4553 Enter_Overloaded_Entity (S);
4554 Set_Homonym (S, Homonym (E));
4555 Check_Dispatching_Operation (S, Empty);
4557 -- If the subprogram is implicit it is hidden by the previous
4558 -- declaration. However if it is dispatching, it must appear in
4559 -- the dispatch table anyway, because it can be dispatched to
4560 -- even if it cannot be called directly.
4562 elsif Present (Alias (S))
4563 and then not Comes_From_Source (S)
4565 Set_Scope (S, Current_Scope);
4567 if Is_Dispatching_Operation (Alias (S)) then
4568 Check_Dispatching_Operation (S, Empty);
4574 Error_Msg_Sloc := Sloc (E);
4575 Error_Msg_N ("& conflicts with declaration#", S);
4577 -- Useful additional warning
4579 if Is_Generic_Unit (E) then
4580 Error_Msg_N ("\previous generic unit cannot be overloaded", S);
4586 -- E exists and is overloadable
4589 -- Loop through E and its homonyms to determine if any of them
4590 -- is the candidate for overriding by S.
4592 while Present (E) loop
4594 -- Definitely not interesting if not in the current scope
4596 if Scope (E) /= Current_Scope then
4599 -- Check if we have type conformance
4601 elsif Type_Conformant (E, S) then
4603 -- If the old and new entities have the same profile and
4604 -- one is not the body of the other, then this is an error,
4605 -- unless one of them is implicitly declared.
4607 -- There are some cases when both can be implicit, for example
4608 -- when both a literal and a function that overrides it are
4609 -- inherited in a derivation, or when an inhertited operation
4610 -- of a tagged full type overrides the ineherited operation of
4611 -- a private extension. Ada 83 had a special rule for the
4612 -- the literal case. In Ada95, the later implicit operation
4613 -- hides the former, and the literal is always the former.
4614 -- In the odd case where both are derived operations declared
4615 -- at the same point, both operations should be declared,
4616 -- and in that case we bypass the following test and proceed
4617 -- to the next part (this can only occur for certain obscure
4618 -- cases involving homographs in instances and can't occur for
4619 -- dispatching operations ???). Note that the following
4620 -- condition is less than clear. For example, it's not at
4621 -- all clear why there's a test for E_Entry here. ???
4623 if Present (Alias (S))
4624 and then (No (Alias (E))
4625 or else Comes_From_Source (E)
4626 or else Is_Dispatching_Operation (E))
4628 (Ekind (E) = E_Entry
4629 or else Ekind (E) /= E_Enumeration_Literal)
4631 -- When an derived operation is overloaded it may be due
4632 -- to the fact that the full view of a private extension
4633 -- re-inherits. It has to be dealt with.
4635 if Is_Package (Current_Scope)
4636 and then In_Private_Part (Current_Scope)
4638 Check_Operation_From_Private_View (S, E);
4641 -- In any case the implicit operation remains hidden by
4642 -- the existing declaration, which is overriding.
4644 Set_Is_Overriding_Operation (E);
4647 -- Within an instance, the renaming declarations for
4648 -- actual subprograms may become ambiguous, but they do
4649 -- not hide each other.
4651 elsif Ekind (E) /= E_Entry
4652 and then not Comes_From_Source (E)
4653 and then not Is_Generic_Instance (E)
4654 and then (Present (Alias (E))
4655 or else Is_Intrinsic_Subprogram (E))
4656 and then (not In_Instance
4657 or else No (Parent (E))
4658 or else Nkind (Unit_Declaration_Node (E)) /=
4659 N_Subprogram_Renaming_Declaration)
4661 -- A subprogram child unit is not allowed to override
4662 -- an inherited subprogram (10.1.1(20)).
4664 if Is_Child_Unit (S) then
4666 ("child unit overrides inherited subprogram in parent",
4671 if Is_Non_Overriding_Operation (E, S) then
4672 Enter_Overloaded_Entity (S);
4673 if not Present (Derived_Type)
4674 or else Is_Tagged_Type (Derived_Type)
4676 Check_Dispatching_Operation (S, Empty);
4682 -- E is a derived operation or an internal operator which
4683 -- is being overridden. Remove E from further visibility.
4684 -- Furthermore, if E is a dispatching operation, it must be
4685 -- replaced in the list of primitive operations of its type
4686 -- (see Override_Dispatching_Operation).
4692 Prev := First_Entity (Current_Scope);
4694 while Present (Prev)
4695 and then Next_Entity (Prev) /= E
4700 -- It is possible for E to be in the current scope and
4701 -- yet not in the entity chain. This can only occur in a
4702 -- generic context where E is an implicit concatenation
4703 -- in the formal part, because in a generic body the
4704 -- entity chain starts with the formals.
4707 (Present (Prev) or else Chars (E) = Name_Op_Concat);
4709 -- E must be removed both from the entity_list of the
4710 -- current scope, and from the visibility chain
4712 if Debug_Flag_E then
4713 Write_Str ("Override implicit operation ");
4714 Write_Int (Int (E));
4718 -- If E is a predefined concatenation, it stands for four
4719 -- different operations. As a result, a single explicit
4720 -- declaration does not hide it. In a possible ambiguous
4721 -- situation, Disambiguate chooses the user-defined op,
4722 -- so it is correct to retain the previous internal one.
4724 if Chars (E) /= Name_Op_Concat
4725 or else Ekind (E) /= E_Operator
4727 -- For nondispatching derived operations that are
4728 -- overridden by a subprogram declared in the private
4729 -- part of a package, we retain the derived subprogram
4730 -- but mark it as not immediately visible. If the
4731 -- derived operation was declared in the visible part
4732 -- then this ensures that it will still be visible
4733 -- outside the package with the proper signature
4734 -- (calls from outside must also be directed to this
4735 -- version rather than the overriding one, unlike the
4736 -- dispatching case). Calls from inside the package
4737 -- will still resolve to the overriding subprogram
4738 -- since the derived one is marked as not visible
4739 -- within the package.
4741 -- If the private operation is dispatching, we achieve
4742 -- the overriding by keeping the implicit operation
4743 -- but setting its alias to be the overring one. In
4744 -- this fashion the proper body is executed in all
4745 -- cases, but the original signature is used outside
4748 -- If the overriding is not in the private part, we
4749 -- remove the implicit operation altogether.
4751 if Is_Private_Declaration (S) then
4753 if not Is_Dispatching_Operation (E) then
4754 Set_Is_Immediately_Visible (E, False);
4757 -- work done in Override_Dispatching_Operation.
4763 -- Find predecessor of E in Homonym chain
4765 if E = Current_Entity (E) then
4768 Prev_Vis := Current_Entity (E);
4769 while Homonym (Prev_Vis) /= E loop
4770 Prev_Vis := Homonym (Prev_Vis);
4774 if Prev_Vis /= Empty then
4776 -- Skip E in the visibility chain
4778 Set_Homonym (Prev_Vis, Homonym (E));
4781 Set_Name_Entity_Id (Chars (E), Homonym (E));
4784 Set_Next_Entity (Prev, Next_Entity (E));
4786 if No (Next_Entity (Prev)) then
4787 Set_Last_Entity (Current_Scope, Prev);
4793 Enter_Overloaded_Entity (S);
4794 Set_Is_Overriding_Operation (S);
4796 if Is_Dispatching_Operation (E) then
4798 -- An overriding dispatching subprogram inherits
4799 -- the convention of the overridden subprogram
4802 Set_Convention (S, Convention (E));
4804 Check_Dispatching_Operation (S, E);
4806 Check_Dispatching_Operation (S, Empty);
4809 Maybe_Primitive_Operation (Overriding => True);
4810 goto Check_Inequality;
4813 -- Apparent redeclarations in instances can occur when two
4814 -- formal types get the same actual type. The subprograms in
4815 -- in the instance are legal, even if not callable from the
4816 -- outside. Calls from within are disambiguated elsewhere.
4817 -- For dispatching operations in the visible part, the usual
4818 -- rules apply, and operations with the same profile are not
4821 elsif (In_Instance_Visible_Part
4822 and then not Is_Dispatching_Operation (E))
4823 or else In_Instance_Not_Visible
4827 -- Here we have a real error (identical profile)
4830 Error_Msg_Sloc := Sloc (E);
4832 -- Avoid cascaded errors if the entity appears in
4833 -- subsequent calls.
4835 Set_Scope (S, Current_Scope);
4837 Error_Msg_N ("& conflicts with declaration#", S);
4839 if Is_Generic_Instance (S)
4840 and then not Has_Completion (E)
4843 ("\instantiation cannot provide body for it", S);
4857 -- On exit, we know that S is a new entity
4859 Enter_Overloaded_Entity (S);
4860 Maybe_Primitive_Operation;
4862 -- If S is a derived operation for an untagged type then
4863 -- by definition it's not a dispatching operation (even
4864 -- if the parent operation was dispatching), so we don't
4865 -- call Check_Dispatching_Operation in that case.
4867 if not Present (Derived_Type)
4868 or else Is_Tagged_Type (Derived_Type)
4870 Check_Dispatching_Operation (S, Empty);
4874 -- If this is a user-defined equality operator that is not
4875 -- a derived subprogram, create the corresponding inequality.
4876 -- If the operation is dispatching, the expansion is done
4877 -- elsewhere, and we do not create an explicit inequality
4880 <<Check_Inequality>>
4881 if Chars (S) = Name_Op_Eq
4882 and then Etype (S) = Standard_Boolean
4883 and then Present (Parent (S))
4884 and then not Is_Dispatching_Operation (S)
4886 Make_Inequality_Operator (S);
4888 end New_Overloaded_Entity;
4890 ---------------------
4891 -- Process_Formals --
4892 ---------------------
4894 procedure Process_Formals
4896 Related_Nod : Node_Id)
4898 Param_Spec : Node_Id;
4900 Formal_Type : Entity_Id;
4904 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
4905 -- Check whether the default has a class-wide type. After analysis
4906 -- the default has the type of the formal, so we must also check
4907 -- explicitly for an access attribute.
4909 ---------------------------
4910 -- Is_Class_Wide_Default --
4911 ---------------------------
4913 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
4915 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
4916 or else (Nkind (D) = N_Attribute_Reference
4917 and then Attribute_Name (D) = Name_Access
4918 and then Is_Class_Wide_Type (Etype (Prefix (D))));
4919 end Is_Class_Wide_Default;
4921 -- Start of processing for Process_Formals
4924 -- In order to prevent premature use of the formals in the same formal
4925 -- part, the Ekind is left undefined until all default expressions are
4926 -- analyzed. The Ekind is established in a separate loop at the end.
4928 Param_Spec := First (T);
4930 while Present (Param_Spec) loop
4932 Formal := Defining_Identifier (Param_Spec);
4933 Enter_Name (Formal);
4935 -- Case of ordinary parameters
4937 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
4938 Find_Type (Parameter_Type (Param_Spec));
4939 Ptype := Parameter_Type (Param_Spec);
4941 if Ptype = Error then
4945 Formal_Type := Entity (Ptype);
4947 if Ekind (Formal_Type) = E_Incomplete_Type
4948 or else (Is_Class_Wide_Type (Formal_Type)
4949 and then Ekind (Root_Type (Formal_Type)) =
4952 -- Ada 0Y (AI-50217): Incomplete tagged types that are made
4953 -- visible through a limited with_clause are valid formal
4956 if From_With_Type (Formal_Type)
4957 and then Is_Tagged_Type (Formal_Type)
4961 elsif Nkind (Parent (T)) /= N_Access_Function_Definition
4962 and then Nkind (Parent (T)) /= N_Access_Procedure_Definition
4964 Error_Msg_N ("invalid use of incomplete type", Param_Spec);
4967 elsif Ekind (Formal_Type) = E_Void then
4968 Error_Msg_NE ("premature use of&",
4969 Parameter_Type (Param_Spec), Formal_Type);
4972 -- Ada 0Y (AI-231): Create and decorate an internal subtype
4973 -- declaration corresponding to the null-excluding type of the
4974 -- formal in the enclosing scope. In addition, replace the
4975 -- parameter type of the formal to this internal subtype.
4977 if Null_Exclusion_Present (Param_Spec) then
4979 Loc : constant Source_Ptr := Sloc (Param_Spec);
4981 Anon : constant Entity_Id :=
4982 Make_Defining_Identifier (Loc,
4983 Chars => New_Internal_Name ('S'));
4985 Curr_Scope : constant Scope_Stack_Entry :=
4986 Scope_Stack.Table (Scope_Stack.Last);
4988 Ptype : constant Node_Id := Parameter_Type (Param_Spec);
4990 P : Node_Id := Parent (Parent (Related_Nod));
4993 Set_Is_Internal (Anon);
4996 Make_Subtype_Declaration (Loc,
4997 Defining_Identifier => Anon,
4998 Null_Exclusion_Present => True,
4999 Subtype_Indication =>
5000 New_Occurrence_Of (Etype (Ptype), Loc));
5002 -- Propagate the null-excluding attribute to the new entity
5004 if Null_Exclusion_Present (Param_Spec) then
5005 Set_Null_Exclusion_Present (Param_Spec, False);
5006 Set_Can_Never_Be_Null (Anon);
5009 Mark_Rewrite_Insertion (Decl);
5011 -- Insert the new declaration in the nearest enclosing scope
5013 while not Has_Declarations (P) loop
5017 Prepend (Decl, Declarations (P));
5019 Rewrite (Ptype, New_Occurrence_Of (Anon, Loc));
5020 Mark_Rewrite_Insertion (Ptype);
5022 -- Analyze the new declaration in the context of the
5025 Scope_Stack.Decrement_Last;
5027 Scope_Stack.Append (Curr_Scope);
5029 Formal_Type := Anon;
5033 -- Ada 0Y (AI-231): Static checks
5035 if Null_Exclusion_Present (Param_Spec)
5036 or else Can_Never_Be_Null (Entity (Ptype))
5038 Null_Exclusion_Static_Checks (Param_Spec);
5041 -- An access formal type
5045 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
5050 AD : constant Node_Id :=
5051 Access_To_Subprogram_Definition
5052 (Parameter_Type (Param_Spec));
5054 if Present (AD) and then Protected_Present (AD) then
5056 Replace_Anonymous_Access_To_Protected_Subprogram
5057 (Param_Spec, Formal_Type);
5062 Set_Etype (Formal, Formal_Type);
5063 Default := Expression (Param_Spec);
5065 if Present (Default) then
5066 if Out_Present (Param_Spec) then
5068 ("default initialization only allowed for IN parameters",
5072 -- Do the special preanalysis of the expression (see section on
5073 -- "Handling of Default Expressions" in the spec of package Sem).
5075 Analyze_Per_Use_Expression (Default, Formal_Type);
5077 -- Check that the designated type of an access parameter's
5078 -- default is not a class-wide type unless the parameter's
5079 -- designated type is also class-wide.
5081 if Ekind (Formal_Type) = E_Anonymous_Access_Type
5082 and then Is_Class_Wide_Default (Default)
5083 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
5086 ("access to class-wide expression not allowed here", Default);
5094 -- Now set the kind (mode) of each formal
5096 Param_Spec := First (T);
5098 while Present (Param_Spec) loop
5099 Formal := Defining_Identifier (Param_Spec);
5100 Set_Formal_Mode (Formal);
5102 if Ekind (Formal) = E_In_Parameter then
5103 Set_Default_Value (Formal, Expression (Param_Spec));
5105 if Present (Expression (Param_Spec)) then
5106 Default := Expression (Param_Spec);
5108 if Is_Scalar_Type (Etype (Default)) then
5110 (Parameter_Type (Param_Spec)) /= N_Access_Definition
5112 Formal_Type := Entity (Parameter_Type (Param_Spec));
5115 Formal_Type := Access_Definition
5116 (Related_Nod, Parameter_Type (Param_Spec));
5119 Apply_Scalar_Range_Check (Default, Formal_Type);
5127 end Process_Formals;
5129 ----------------------------
5130 -- Reference_Body_Formals --
5131 ----------------------------
5133 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
5138 if Error_Posted (Spec) then
5142 Fs := First_Formal (Spec);
5143 Fb := First_Formal (Bod);
5145 while Present (Fs) loop
5146 Generate_Reference (Fs, Fb, 'b');
5149 Style.Check_Identifier (Fb, Fs);
5152 Set_Spec_Entity (Fb, Fs);
5153 Set_Referenced (Fs, False);
5157 end Reference_Body_Formals;
5159 -------------------------
5160 -- Set_Actual_Subtypes --
5161 -------------------------
5163 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
5164 Loc : constant Source_Ptr := Sloc (N);
5168 First_Stmt : Node_Id := Empty;
5169 AS_Needed : Boolean;
5172 -- If this is an emtpy initialization procedure, no need to create
5173 -- actual subtypes (small optimization).
5175 if Ekind (Subp) = E_Procedure
5176 and then Is_Null_Init_Proc (Subp)
5181 Formal := First_Formal (Subp);
5182 while Present (Formal) loop
5183 T := Etype (Formal);
5185 -- We never need an actual subtype for a constrained formal.
5187 if Is_Constrained (T) then
5190 -- If we have unknown discriminants, then we do not need an
5191 -- actual subtype, or more accurately we cannot figure it out!
5192 -- Note that all class-wide types have unknown discriminants.
5194 elsif Has_Unknown_Discriminants (T) then
5197 -- At this stage we have an unconstrained type that may need
5198 -- an actual subtype. For sure the actual subtype is needed
5199 -- if we have an unconstrained array type.
5201 elsif Is_Array_Type (T) then
5204 -- The only other case which needs an actual subtype is an
5205 -- unconstrained record type which is an IN parameter (we
5206 -- cannot generate actual subtypes for the OUT or IN OUT case,
5207 -- since an assignment can change the discriminant values.
5208 -- However we exclude the case of initialization procedures,
5209 -- since discriminants are handled very specially in this context,
5210 -- see the section entitled "Handling of Discriminants" in Einfo.
5211 -- We also exclude the case of Discrim_SO_Functions (functions
5212 -- used in front end layout mode for size/offset values), since
5213 -- in such functions only discriminants are referenced, and not
5214 -- only are such subtypes not needed, but they cannot always
5215 -- be generated, because of order of elaboration issues.
5217 elsif Is_Record_Type (T)
5218 and then Ekind (Formal) = E_In_Parameter
5219 and then Chars (Formal) /= Name_uInit
5220 and then not Is_Discrim_SO_Function (Subp)
5224 -- All other cases do not need an actual subtype
5230 -- Generate actual subtypes for unconstrained arrays and
5231 -- unconstrained discriminated records.
5234 if Nkind (N) = N_Accept_Statement then
5236 -- If expansion is active, The formal is replaced by a local
5237 -- variable that renames the corresponding entry of the
5238 -- parameter block, and it is this local variable that may
5239 -- require an actual subtype.
5241 if Expander_Active then
5242 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
5244 Decl := Build_Actual_Subtype (T, Formal);
5247 if Present (Handled_Statement_Sequence (N)) then
5249 First (Statements (Handled_Statement_Sequence (N)));
5250 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
5251 Mark_Rewrite_Insertion (Decl);
5253 -- If the accept statement has no body, there will be
5254 -- no reference to the actuals, so no need to compute
5261 Decl := Build_Actual_Subtype (T, Formal);
5262 Prepend (Decl, Declarations (N));
5263 Mark_Rewrite_Insertion (Decl);
5266 -- The declaration uses the bounds of an existing object,
5267 -- and therefore needs no constraint checks.
5269 Analyze (Decl, Suppress => All_Checks);
5271 -- We need to freeze manually the generated type when it is
5272 -- inserted anywhere else than in a declarative part.
5274 if Present (First_Stmt) then
5275 Insert_List_Before_And_Analyze (First_Stmt,
5276 Freeze_Entity (Defining_Identifier (Decl), Loc));
5279 if Nkind (N) = N_Accept_Statement
5280 and then Expander_Active
5282 Set_Actual_Subtype (Renamed_Object (Formal),
5283 Defining_Identifier (Decl));
5285 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
5289 Next_Formal (Formal);
5291 end Set_Actual_Subtypes;
5293 ---------------------
5294 -- Set_Formal_Mode --
5295 ---------------------
5297 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
5298 Spec : constant Node_Id := Parent (Formal_Id);
5301 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
5302 -- since we ensure that corresponding actuals are always valid at the
5303 -- point of the call.
5305 if Out_Present (Spec) then
5306 if Ekind (Scope (Formal_Id)) = E_Function
5307 or else Ekind (Scope (Formal_Id)) = E_Generic_Function
5309 Error_Msg_N ("functions can only have IN parameters", Spec);
5310 Set_Ekind (Formal_Id, E_In_Parameter);
5312 elsif In_Present (Spec) then
5313 Set_Ekind (Formal_Id, E_In_Out_Parameter);
5316 Set_Ekind (Formal_Id, E_Out_Parameter);
5317 Set_Never_Set_In_Source (Formal_Id, True);
5318 Set_Is_True_Constant (Formal_Id, False);
5319 Set_Current_Value (Formal_Id, Empty);
5323 Set_Ekind (Formal_Id, E_In_Parameter);
5326 -- Set Is_Known_Non_Null for access parameters since the language
5327 -- guarantees that access parameters are always non-null. We also
5328 -- set Can_Never_Be_Null, since there is no way to change the value.
5330 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
5332 -- Ada 0Y (AI-231): This behaviour has been modified in Ada 0Y.
5333 -- It is only forced if the null_exclusion appears.
5335 if not Extensions_Allowed
5336 or else Null_Exclusion_Present (Spec)
5338 Set_Is_Known_Non_Null (Formal_Id);
5339 Set_Can_Never_Be_Null (Formal_Id);
5343 Set_Mechanism (Formal_Id, Default_Mechanism);
5344 Set_Formal_Validity (Formal_Id);
5345 end Set_Formal_Mode;
5347 -------------------------
5348 -- Set_Formal_Validity --
5349 -------------------------
5351 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
5353 -- If no validity checking, then we cannot assume anything about
5354 -- the validity of parameters, since we do not know there is any
5355 -- checking of the validity on the call side.
5357 if not Validity_Checks_On then
5360 -- If validity checking for parameters is enabled, this means we are
5361 -- not supposed to make any assumptions about argument values.
5363 elsif Validity_Check_Parameters then
5366 -- If we are checking in parameters, we will assume that the caller is
5367 -- also checking parameters, so we can assume the parameter is valid.
5369 elsif Ekind (Formal_Id) = E_In_Parameter
5370 and then Validity_Check_In_Params
5372 Set_Is_Known_Valid (Formal_Id, True);
5374 -- Similar treatment for IN OUT parameters
5376 elsif Ekind (Formal_Id) = E_In_Out_Parameter
5377 and then Validity_Check_In_Out_Params
5379 Set_Is_Known_Valid (Formal_Id, True);
5381 end Set_Formal_Validity;
5383 ------------------------
5384 -- Subtype_Conformant --
5385 ------------------------
5387 function Subtype_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
5391 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result);
5393 end Subtype_Conformant;
5395 ---------------------
5396 -- Type_Conformant --
5397 ---------------------
5399 function Type_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
5402 Check_Conformance (New_Id, Old_Id, Type_Conformant, False, Result);
5404 end Type_Conformant;
5406 -------------------------------
5407 -- Valid_Operator_Definition --
5408 -------------------------------
5410 procedure Valid_Operator_Definition (Designator : Entity_Id) is
5413 Id : constant Name_Id := Chars (Designator);
5417 F := First_Formal (Designator);
5419 while Present (F) loop
5422 if Present (Default_Value (F)) then
5424 ("default values not allowed for operator parameters",
5431 -- Verify that user-defined operators have proper number of arguments
5432 -- First case of operators which can only be unary
5435 or else Id = Name_Op_Abs
5439 -- Case of operators which can be unary or binary
5441 elsif Id = Name_Op_Add
5442 or Id = Name_Op_Subtract
5444 N_OK := (N in 1 .. 2);
5446 -- All other operators can only be binary
5454 ("incorrect number of arguments for operator", Designator);
5458 and then Base_Type (Etype (Designator)) = Standard_Boolean
5459 and then not Is_Intrinsic_Subprogram (Designator)
5462 ("explicit definition of inequality not allowed", Designator);
5464 end Valid_Operator_Definition;