1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2011, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Checks; use Checks;
28 with Debug; use Debug;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Errout; use Errout;
32 with Expander; use Expander;
33 with Exp_Ch6; use Exp_Ch6;
34 with Exp_Ch7; use Exp_Ch7;
35 with Exp_Ch9; use Exp_Ch9;
36 with Exp_Disp; use Exp_Disp;
37 with Exp_Tss; use Exp_Tss;
38 with Exp_Util; use Exp_Util;
39 with Fname; use Fname;
40 with Freeze; use Freeze;
41 with Itypes; use Itypes;
42 with Lib.Xref; use Lib.Xref;
43 with Layout; use Layout;
44 with Namet; use Namet;
46 with Nlists; use Nlists;
47 with Nmake; use Nmake;
49 with Output; use Output;
50 with Restrict; use Restrict;
51 with Rident; use Rident;
52 with Rtsfind; use Rtsfind;
54 with Sem_Aux; use Sem_Aux;
55 with Sem_Cat; use Sem_Cat;
56 with Sem_Ch3; use Sem_Ch3;
57 with Sem_Ch4; use Sem_Ch4;
58 with Sem_Ch5; use Sem_Ch5;
59 with Sem_Ch8; use Sem_Ch8;
60 with Sem_Ch10; use Sem_Ch10;
61 with Sem_Ch12; use Sem_Ch12;
62 with Sem_Ch13; use Sem_Ch13;
63 with Sem_Disp; use Sem_Disp;
64 with Sem_Dist; use Sem_Dist;
65 with Sem_Elim; use Sem_Elim;
66 with Sem_Eval; use Sem_Eval;
67 with Sem_Mech; use Sem_Mech;
68 with Sem_Prag; use Sem_Prag;
69 with Sem_Res; use Sem_Res;
70 with Sem_Util; use Sem_Util;
71 with Sem_Type; use Sem_Type;
72 with Sem_Warn; use Sem_Warn;
73 with Sinput; use Sinput;
74 with Stand; use Stand;
75 with Sinfo; use Sinfo;
76 with Sinfo.CN; use Sinfo.CN;
77 with Snames; use Snames;
78 with Stringt; use Stringt;
80 with Stylesw; use Stylesw;
81 with Tbuild; use Tbuild;
82 with Uintp; use Uintp;
83 with Urealp; use Urealp;
84 with Validsw; use Validsw;
86 package body Sem_Ch6 is
88 May_Hide_Profile : Boolean := False;
89 -- This flag is used to indicate that two formals in two subprograms being
90 -- checked for conformance differ only in that one is an access parameter
91 -- while the other is of a general access type with the same designated
92 -- type. In this case, if the rest of the signatures match, a call to
93 -- either subprogram may be ambiguous, which is worth a warning. The flag
94 -- is set in Compatible_Types, and the warning emitted in
95 -- New_Overloaded_Entity.
97 -----------------------
98 -- Local Subprograms --
99 -----------------------
101 procedure Analyze_Return_Statement (N : Node_Id);
102 -- Common processing for simple and extended return statements
104 procedure Analyze_Function_Return (N : Node_Id);
105 -- Subsidiary to Analyze_Return_Statement. Called when the return statement
106 -- applies to a [generic] function.
108 procedure Analyze_Return_Type (N : Node_Id);
109 -- Subsidiary to Process_Formals: analyze subtype mark in function
110 -- specification in a context where the formals are visible and hide
113 procedure Analyze_Subprogram_Body_Helper (N : Node_Id);
114 -- Does all the real work of Analyze_Subprogram_Body. This is split out so
115 -- that we can use RETURN but not skip the debug output at the end.
117 procedure Analyze_Generic_Subprogram_Body (N : Node_Id; Gen_Id : Entity_Id);
118 -- Analyze a generic subprogram body. N is the body to be analyzed, and
119 -- Gen_Id is the defining entity Id for the corresponding spec.
121 procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id);
122 -- If a subprogram has pragma Inline and inlining is active, use generic
123 -- machinery to build an unexpanded body for the subprogram. This body is
124 -- subsequently used for inline expansions at call sites. If subprogram can
125 -- be inlined (depending on size and nature of local declarations) this
126 -- function returns true. Otherwise subprogram body is treated normally.
127 -- If proper warnings are enabled and the subprogram contains a construct
128 -- that cannot be inlined, the offending construct is flagged accordingly.
130 function Can_Override_Operator (Subp : Entity_Id) return Boolean;
131 -- Returns true if Subp can override a predefined operator.
133 procedure Check_Conformance
136 Ctype : Conformance_Type;
138 Conforms : out Boolean;
139 Err_Loc : Node_Id := Empty;
140 Get_Inst : Boolean := False;
141 Skip_Controlling_Formals : Boolean := False);
142 -- Given two entities, this procedure checks that the profiles associated
143 -- with these entities meet the conformance criterion given by the third
144 -- parameter. If they conform, Conforms is set True and control returns
145 -- to the caller. If they do not conform, Conforms is set to False, and
146 -- in addition, if Errmsg is True on the call, proper messages are output
147 -- to complain about the conformance failure. If Err_Loc is non_Empty
148 -- the error messages are placed on Err_Loc, if Err_Loc is empty, then
149 -- error messages are placed on the appropriate part of the construct
150 -- denoted by New_Id. If Get_Inst is true, then this is a mode conformance
151 -- against a formal access-to-subprogram type so Get_Instance_Of must
154 procedure Check_Subprogram_Order (N : Node_Id);
155 -- N is the N_Subprogram_Body node for a subprogram. This routine applies
156 -- the alpha ordering rule for N if this ordering requirement applicable.
158 procedure Check_Returns
162 Proc : Entity_Id := Empty);
163 -- Called to check for missing return statements in a function body, or for
164 -- returns present in a procedure body which has No_Return set. HSS is the
165 -- handled statement sequence for the subprogram body. This procedure
166 -- checks all flow paths to make sure they either have return (Mode = 'F',
167 -- used for functions) or do not have a return (Mode = 'P', used for
168 -- No_Return procedures). The flag Err is set if there are any control
169 -- paths not explicitly terminated by a return in the function case, and is
170 -- True otherwise. Proc is the entity for the procedure case and is used
171 -- in posting the warning message.
173 procedure Check_Untagged_Equality (Eq_Op : Entity_Id);
174 -- In Ada 2012, a primitive equality operator on an untagged record type
175 -- must appear before the type is frozen, and have the same visibility as
176 -- that of the type. This procedure checks that this rule is met, and
177 -- otherwise emits an error on the subprogram declaration and a warning
178 -- on the earlier freeze point if it is easy to locate.
180 procedure Enter_Overloaded_Entity (S : Entity_Id);
181 -- This procedure makes S, a new overloaded entity, into the first visible
182 -- entity with that name.
184 procedure Install_Entity (E : Entity_Id);
185 -- Make single entity visible (used for generic formals as well)
187 function Is_Non_Overriding_Operation
189 New_E : Entity_Id) return Boolean;
190 -- Enforce the rule given in 12.3(18): a private operation in an instance
191 -- overrides an inherited operation only if the corresponding operation
192 -- was overriding in the generic. This can happen for primitive operations
193 -- of types derived (in the generic unit) from formal private or formal
196 procedure Make_Inequality_Operator (S : Entity_Id);
197 -- Create the declaration for an inequality operator that is implicitly
198 -- created by a user-defined equality operator that yields a boolean.
200 procedure May_Need_Actuals (Fun : Entity_Id);
201 -- Flag functions that can be called without parameters, i.e. those that
202 -- have no parameters, or those for which defaults exist for all parameters
204 procedure Process_PPCs
207 Body_Id : Entity_Id);
208 -- Called from Analyze[_Generic]_Subprogram_Body to deal with scanning post
209 -- conditions for the body and assembling and inserting the _postconditions
210 -- procedure. N is the node for the subprogram body and Body_Id/Spec_Id are
211 -- the entities for the body and separate spec (if there is no separate
212 -- spec, Spec_Id is Empty). Note that invariants and predicates may also
213 -- provide postconditions, and are also handled in this procedure.
215 procedure Set_Formal_Validity (Formal_Id : Entity_Id);
216 -- Formal_Id is an formal parameter entity. This procedure deals with
217 -- setting the proper validity status for this entity, which depends on
218 -- the kind of parameter and the validity checking mode.
220 ---------------------------------------------
221 -- Analyze_Abstract_Subprogram_Declaration --
222 ---------------------------------------------
224 procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is
225 Designator : constant Entity_Id :=
226 Analyze_Subprogram_Specification (Specification (N));
227 Scop : constant Entity_Id := Current_Scope;
230 Check_SPARK_Restriction ("abstract subprogram is not allowed", N);
232 Generate_Definition (Designator);
233 Set_Contract (Designator, Make_Contract (Sloc (Designator)));
234 Set_Is_Abstract_Subprogram (Designator);
235 New_Overloaded_Entity (Designator);
236 Check_Delayed_Subprogram (Designator);
238 Set_Categorization_From_Scope (Designator, Scop);
240 if Ekind (Scope (Designator)) = E_Protected_Type then
242 ("abstract subprogram not allowed in protected type", N);
244 -- Issue a warning if the abstract subprogram is neither a dispatching
245 -- operation nor an operation that overrides an inherited subprogram or
246 -- predefined operator, since this most likely indicates a mistake.
248 elsif Warn_On_Redundant_Constructs
249 and then not Is_Dispatching_Operation (Designator)
250 and then not Present (Overridden_Operation (Designator))
251 and then (not Is_Operator_Symbol_Name (Chars (Designator))
252 or else Scop /= Scope (Etype (First_Formal (Designator))))
255 ("?abstract subprogram is not dispatching or overriding", N);
258 Generate_Reference_To_Formals (Designator);
259 Check_Eliminated (Designator);
261 if Has_Aspects (N) then
262 Analyze_Aspect_Specifications (N, Designator);
264 end Analyze_Abstract_Subprogram_Declaration;
266 ---------------------------------
267 -- Analyze_Expression_Function --
268 ---------------------------------
270 procedure Analyze_Expression_Function (N : Node_Id) is
271 Loc : constant Source_Ptr := Sloc (N);
272 LocX : constant Source_Ptr := Sloc (Expression (N));
273 Def_Id : constant Entity_Id := Defining_Entity (Specification (N));
277 Prev : constant Entity_Id := Current_Entity_In_Scope (Def_Id);
278 -- If the expression is a completion, Prev is the entity whose
279 -- declaration is completed.
282 -- This is one of the occasions on which we transform the tree during
283 -- semantic analysis. If this is a completion, transform the expression
284 -- function into an equivalent subprogram body, and analyze it.
286 -- Expression functions are inlined unconditionally. The back-end will
287 -- determine whether this is possible.
289 Inline_Processing_Required := True;
292 Make_Subprogram_Body (Loc,
293 Specification => Specification (N),
294 Declarations => Empty_List,
295 Handled_Statement_Sequence =>
296 Make_Handled_Sequence_Of_Statements (LocX,
297 Statements => New_List (
298 Make_Simple_Return_Statement (LocX,
299 Expression => Expression (N)))));
302 and then Ekind (Prev) = E_Generic_Function
304 -- If the expression completes a generic subprogram, we must create a
305 -- separate node for the body, because at instantiation the original
306 -- node of the generic copy must be a generic subprogram body, and
307 -- cannot be a expression function. Otherwise we just rewrite the
308 -- expression with the non-generic body.
310 Insert_After (N, New_Body);
311 Rewrite (N, Make_Null_Statement (Loc));
314 Set_Is_Inlined (Prev);
316 elsif Present (Prev) then
317 Rewrite (N, New_Body);
318 Set_Is_Inlined (Prev);
321 -- If this is not a completion, create both a declaration and a body,
322 -- so that the expression can be inlined whenever possible.
326 Make_Subprogram_Declaration (Loc,
327 Specification => Specification (N));
328 Rewrite (N, New_Decl);
330 Set_Is_Inlined (Defining_Entity (New_Decl));
332 -- Create new set of formals for specification in body.
334 Set_Specification (New_Body,
335 Make_Function_Specification (Loc,
336 Defining_Unit_Name =>
337 Make_Defining_Identifier (Loc, Chars (Defining_Entity (N))),
338 Parameter_Specifications =>
339 Copy_Parameter_List (Defining_Entity (New_Decl)),
341 New_Copy_Tree (Result_Definition (Specification (New_Decl)))));
343 Insert_After (N, New_Body);
346 end Analyze_Expression_Function;
348 ----------------------------------------
349 -- Analyze_Extended_Return_Statement --
350 ----------------------------------------
352 procedure Analyze_Extended_Return_Statement (N : Node_Id) is
354 Analyze_Return_Statement (N);
355 end Analyze_Extended_Return_Statement;
357 ----------------------------
358 -- Analyze_Function_Call --
359 ----------------------------
361 procedure Analyze_Function_Call (N : Node_Id) is
362 P : constant Node_Id := Name (N);
363 Actuals : constant List_Id := Parameter_Associations (N);
369 -- A call of the form A.B (X) may be an Ada05 call, which is rewritten
370 -- as B (A, X). If the rewriting is successful, the call has been
371 -- analyzed and we just return.
373 if Nkind (P) = N_Selected_Component
374 and then Name (N) /= P
375 and then Is_Rewrite_Substitution (N)
376 and then Present (Etype (N))
381 -- If error analyzing name, then set Any_Type as result type and return
383 if Etype (P) = Any_Type then
384 Set_Etype (N, Any_Type);
388 -- Otherwise analyze the parameters
390 if Present (Actuals) then
391 Actual := First (Actuals);
392 while Present (Actual) loop
394 Check_Parameterless_Call (Actual);
400 end Analyze_Function_Call;
402 -----------------------------
403 -- Analyze_Function_Return --
404 -----------------------------
406 procedure Analyze_Function_Return (N : Node_Id) is
407 Loc : constant Source_Ptr := Sloc (N);
408 Stm_Entity : constant Entity_Id := Return_Statement_Entity (N);
409 Scope_Id : constant Entity_Id := Return_Applies_To (Stm_Entity);
411 R_Type : constant Entity_Id := Etype (Scope_Id);
412 -- Function result subtype
414 procedure Check_Limited_Return (Expr : Node_Id);
415 -- Check the appropriate (Ada 95 or Ada 2005) rules for returning
416 -- limited types. Used only for simple return statements.
417 -- Expr is the expression returned.
419 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id);
420 -- Check that the return_subtype_indication properly matches the result
421 -- subtype of the function, as required by RM-6.5(5.1/2-5.3/2).
423 --------------------------
424 -- Check_Limited_Return --
425 --------------------------
427 procedure Check_Limited_Return (Expr : Node_Id) is
429 -- Ada 2005 (AI-318-02): Return-by-reference types have been
430 -- removed and replaced by anonymous access results. This is an
431 -- incompatibility with Ada 95. Not clear whether this should be
432 -- enforced yet or perhaps controllable with special switch. ???
434 if Is_Limited_Type (R_Type)
435 and then Comes_From_Source (N)
436 and then not In_Instance_Body
437 and then not OK_For_Limited_Init_In_05 (R_Type, Expr)
441 if Ada_Version >= Ada_2005
442 and then not Debug_Flag_Dot_L
443 and then not GNAT_Mode
446 ("(Ada 2005) cannot copy object of a limited type " &
447 "(RM-2005 6.5(5.5/2))", Expr);
449 if Is_Immutably_Limited_Type (R_Type) then
451 ("\return by reference not permitted in Ada 2005", Expr);
454 -- Warn in Ada 95 mode, to give folks a heads up about this
457 -- In GNAT mode, this is just a warning, to allow it to be
458 -- evilly turned off. Otherwise it is a real error.
460 -- In a generic context, simplify the warning because it makes
461 -- no sense to discuss pass-by-reference or copy.
463 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
464 if Inside_A_Generic then
466 ("return of limited object not permitted in Ada2005 "
467 & "(RM-2005 6.5(5.5/2))?", Expr);
469 elsif Is_Immutably_Limited_Type (R_Type) then
471 ("return by reference not permitted in Ada 2005 "
472 & "(RM-2005 6.5(5.5/2))?", Expr);
475 ("cannot copy object of a limited type in Ada 2005 "
476 & "(RM-2005 6.5(5.5/2))?", Expr);
479 -- Ada 95 mode, compatibility warnings disabled
482 return; -- skip continuation messages below
485 if not Inside_A_Generic then
487 ("\consider switching to return of access type", Expr);
488 Explain_Limited_Type (R_Type, Expr);
491 end Check_Limited_Return;
493 -------------------------------------
494 -- Check_Return_Subtype_Indication --
495 -------------------------------------
497 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
498 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
500 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
501 -- Subtype given in the extended return statement (must match R_Type)
503 Subtype_Ind : constant Node_Id :=
504 Object_Definition (Original_Node (Obj_Decl));
506 R_Type_Is_Anon_Access :
508 Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type
510 Ekind (R_Type) = E_Anonymous_Access_Protected_Subprogram_Type
512 Ekind (R_Type) = E_Anonymous_Access_Type;
513 -- True if return type of the function is an anonymous access type
514 -- Can't we make Is_Anonymous_Access_Type in einfo ???
516 R_Stm_Type_Is_Anon_Access :
518 Ekind (R_Stm_Type) = E_Anonymous_Access_Subprogram_Type
520 Ekind (R_Stm_Type) = E_Anonymous_Access_Protected_Subprogram_Type
522 Ekind (R_Stm_Type) = E_Anonymous_Access_Type;
523 -- True if type of the return object is an anonymous access type
526 -- First, avoid cascaded errors
528 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
532 -- "return access T" case; check that the return statement also has
533 -- "access T", and that the subtypes statically match:
534 -- if this is an access to subprogram the signatures must match.
536 if R_Type_Is_Anon_Access then
537 if R_Stm_Type_Is_Anon_Access then
539 Ekind (Designated_Type (R_Stm_Type)) /= E_Subprogram_Type
541 if Base_Type (Designated_Type (R_Stm_Type)) /=
542 Base_Type (Designated_Type (R_Type))
543 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
546 ("subtype must statically match function result subtype",
547 Subtype_Mark (Subtype_Ind));
551 -- For two anonymous access to subprogram types, the
552 -- types themselves must be type conformant.
554 if not Conforming_Types
555 (R_Stm_Type, R_Type, Fully_Conformant)
558 ("subtype must statically match function result subtype",
564 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
567 -- Subtype indication case: check that the return object's type is
568 -- covered by the result type, and that the subtypes statically match
569 -- when the result subtype is constrained. Also handle record types
570 -- with unknown discriminants for which we have built the underlying
571 -- record view. Coverage is needed to allow specific-type return
572 -- objects when the result type is class-wide (see AI05-32).
574 elsif Covers (Base_Type (R_Type), Base_Type (R_Stm_Type))
575 or else (Is_Underlying_Record_View (Base_Type (R_Stm_Type))
579 Underlying_Record_View (Base_Type (R_Stm_Type))))
581 -- A null exclusion may be present on the return type, on the
582 -- function specification, on the object declaration or on the
585 if Is_Access_Type (R_Type)
587 (Can_Never_Be_Null (R_Type)
588 or else Null_Exclusion_Present (Parent (Scope_Id))) /=
589 Can_Never_Be_Null (R_Stm_Type)
592 ("subtype must statically match function result subtype",
596 -- AI05-103: for elementary types, subtypes must statically match
598 if Is_Constrained (R_Type)
599 or else Is_Access_Type (R_Type)
601 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
603 ("subtype must statically match function result subtype",
608 elsif Etype (Base_Type (R_Type)) = R_Stm_Type
609 and then Is_Null_Extension (Base_Type (R_Type))
615 ("wrong type for return_subtype_indication", Subtype_Ind);
617 end Check_Return_Subtype_Indication;
619 ---------------------
620 -- Local Variables --
621 ---------------------
625 -- Start of processing for Analyze_Function_Return
628 Set_Return_Present (Scope_Id);
630 if Nkind (N) = N_Simple_Return_Statement then
631 Expr := Expression (N);
633 -- Guard against a malformed expression. The parser may have tried to
634 -- recover but the node is not analyzable.
636 if Nkind (Expr) = N_Error then
637 Set_Etype (Expr, Any_Type);
638 Expander_Mode_Save_And_Set (False);
642 -- The resolution of a controlled [extension] aggregate associated
643 -- with a return statement creates a temporary which needs to be
644 -- finalized on function exit. Wrap the return statement inside a
645 -- block so that the finalization machinery can detect this case.
646 -- This early expansion is done only when the return statement is
647 -- not part of a handled sequence of statements.
649 if Nkind_In (Expr, N_Aggregate,
650 N_Extension_Aggregate)
651 and then Needs_Finalization (R_Type)
652 and then Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
655 Make_Block_Statement (Loc,
656 Handled_Statement_Sequence =>
657 Make_Handled_Sequence_Of_Statements (Loc,
658 Statements => New_List (Relocate_Node (N)))));
664 Analyze_And_Resolve (Expr, R_Type);
665 Check_Limited_Return (Expr);
668 -- RETURN only allowed in SPARK as the last statement in function
670 if Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
672 (Nkind (Parent (Parent (N))) /= N_Subprogram_Body
673 or else Present (Next (N)))
675 Check_SPARK_Restriction
676 ("RETURN should be the last statement in function", N);
680 Check_SPARK_Restriction ("extended RETURN is not allowed", N);
682 -- Analyze parts specific to extended_return_statement:
685 Obj_Decl : constant Node_Id :=
686 Last (Return_Object_Declarations (N));
688 HSS : constant Node_Id := Handled_Statement_Sequence (N);
691 Expr := Expression (Obj_Decl);
693 -- Note: The check for OK_For_Limited_Init will happen in
694 -- Analyze_Object_Declaration; we treat it as a normal
695 -- object declaration.
697 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
700 Check_Return_Subtype_Indication (Obj_Decl);
702 if Present (HSS) then
705 if Present (Exception_Handlers (HSS)) then
707 -- ???Has_Nested_Block_With_Handler needs to be set.
708 -- Probably by creating an actual N_Block_Statement.
709 -- Probably in Expand.
715 -- Mark the return object as referenced, since the return is an
716 -- implicit reference of the object.
718 Set_Referenced (Defining_Identifier (Obj_Decl));
720 Check_References (Stm_Entity);
724 -- Case of Expr present
728 -- Defend against previous errors
730 and then Nkind (Expr) /= N_Empty
731 and then Present (Etype (Expr))
733 -- Apply constraint check. Note that this is done before the implicit
734 -- conversion of the expression done for anonymous access types to
735 -- ensure correct generation of the null-excluding check associated
736 -- with null-excluding expressions found in return statements.
738 Apply_Constraint_Check (Expr, R_Type);
740 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
741 -- type, apply an implicit conversion of the expression to that type
742 -- to force appropriate static and run-time accessibility checks.
744 if Ada_Version >= Ada_2005
745 and then Ekind (R_Type) = E_Anonymous_Access_Type
747 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
748 Analyze_And_Resolve (Expr, R_Type);
751 -- If the result type is class-wide, then check that the return
752 -- expression's type is not declared at a deeper level than the
753 -- function (RM05-6.5(5.6/2)).
755 if Ada_Version >= Ada_2005
756 and then Is_Class_Wide_Type (R_Type)
758 if Type_Access_Level (Etype (Expr)) >
759 Subprogram_Access_Level (Scope_Id)
762 ("level of return expression type is deeper than " &
763 "class-wide function!", Expr);
767 -- Check incorrect use of dynamically tagged expression
769 if Is_Tagged_Type (R_Type) then
770 Check_Dynamically_Tagged_Expression
776 -- ??? A real run-time accessibility check is needed in cases
777 -- involving dereferences of access parameters. For now we just
778 -- check the static cases.
780 if (Ada_Version < Ada_2005 or else Debug_Flag_Dot_L)
781 and then Is_Immutably_Limited_Type (Etype (Scope_Id))
782 and then Object_Access_Level (Expr) >
783 Subprogram_Access_Level (Scope_Id)
786 -- Suppress the message in a generic, where the rewriting
789 if Inside_A_Generic then
794 Make_Raise_Program_Error (Loc,
795 Reason => PE_Accessibility_Check_Failed));
799 ("cannot return a local value by reference?", N);
801 ("\& will be raised at run time?",
802 N, Standard_Program_Error);
807 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
808 and then Null_Exclusion_Present (Parent (Scope_Id))
810 Apply_Compile_Time_Constraint_Error
812 Msg => "(Ada 2005) null not allowed for "
813 & "null-excluding return?",
814 Reason => CE_Null_Not_Allowed);
817 -- Apply checks suggested by AI05-0144 (dangerous order dependence)
819 Check_Order_Dependence;
821 end Analyze_Function_Return;
823 -------------------------------------
824 -- Analyze_Generic_Subprogram_Body --
825 -------------------------------------
827 procedure Analyze_Generic_Subprogram_Body
831 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
832 Kind : constant Entity_Kind := Ekind (Gen_Id);
838 -- Copy body and disable expansion while analyzing the generic For a
839 -- stub, do not copy the stub (which would load the proper body), this
840 -- will be done when the proper body is analyzed.
842 if Nkind (N) /= N_Subprogram_Body_Stub then
843 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
848 Spec := Specification (N);
850 -- Within the body of the generic, the subprogram is callable, and
851 -- behaves like the corresponding non-generic unit.
853 Body_Id := Defining_Entity (Spec);
855 if Kind = E_Generic_Procedure
856 and then Nkind (Spec) /= N_Procedure_Specification
858 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
861 elsif Kind = E_Generic_Function
862 and then Nkind (Spec) /= N_Function_Specification
864 Error_Msg_N ("invalid body for generic function ", Body_Id);
868 Set_Corresponding_Body (Gen_Decl, Body_Id);
870 if Has_Completion (Gen_Id)
871 and then Nkind (Parent (N)) /= N_Subunit
873 Error_Msg_N ("duplicate generic body", N);
876 Set_Has_Completion (Gen_Id);
879 if Nkind (N) = N_Subprogram_Body_Stub then
880 Set_Ekind (Defining_Entity (Specification (N)), Kind);
882 Set_Corresponding_Spec (N, Gen_Id);
885 if Nkind (Parent (N)) = N_Compilation_Unit then
886 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
889 -- Make generic parameters immediately visible in the body. They are
890 -- needed to process the formals declarations. Then make the formals
891 -- visible in a separate step.
897 First_Ent : Entity_Id;
900 First_Ent := First_Entity (Gen_Id);
903 while Present (E) and then not Is_Formal (E) loop
908 Set_Use (Generic_Formal_Declarations (Gen_Decl));
910 -- Now generic formals are visible, and the specification can be
911 -- analyzed, for subsequent conformance check.
913 Body_Id := Analyze_Subprogram_Specification (Spec);
915 -- Make formal parameters visible
919 -- E is the first formal parameter, we loop through the formals
920 -- installing them so that they will be visible.
922 Set_First_Entity (Gen_Id, E);
923 while Present (E) loop
929 -- Visible generic entity is callable within its own body
931 Set_Ekind (Gen_Id, Ekind (Body_Id));
932 Set_Ekind (Body_Id, E_Subprogram_Body);
933 Set_Convention (Body_Id, Convention (Gen_Id));
934 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
935 Set_Scope (Body_Id, Scope (Gen_Id));
936 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
938 if Nkind (N) = N_Subprogram_Body_Stub then
940 -- No body to analyze, so restore state of generic unit
942 Set_Ekind (Gen_Id, Kind);
943 Set_Ekind (Body_Id, Kind);
945 if Present (First_Ent) then
946 Set_First_Entity (Gen_Id, First_Ent);
953 -- If this is a compilation unit, it must be made visible explicitly,
954 -- because the compilation of the declaration, unlike other library
955 -- unit declarations, does not. If it is not a unit, the following
956 -- is redundant but harmless.
958 Set_Is_Immediately_Visible (Gen_Id);
959 Reference_Body_Formals (Gen_Id, Body_Id);
961 if Is_Child_Unit (Gen_Id) then
962 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
965 Set_Actual_Subtypes (N, Current_Scope);
967 -- Deal with preconditions and postconditions. In formal verification
968 -- mode, we keep pre- and postconditions attached to entities rather
969 -- than inserted in the code, in order to facilitate a distinct
970 -- treatment for them.
972 if not ALFA_Mode then
973 Process_PPCs (N, Gen_Id, Body_Id);
976 -- If the generic unit carries pre- or post-conditions, copy them
977 -- to the original generic tree, so that they are properly added
978 -- to any instantiation.
981 Orig : constant Node_Id := Original_Node (N);
985 Cond := First (Declarations (N));
986 while Present (Cond) loop
987 if Nkind (Cond) = N_Pragma
988 and then Pragma_Name (Cond) = Name_Check
990 Prepend (New_Copy_Tree (Cond), Declarations (Orig));
992 elsif Nkind (Cond) = N_Pragma
993 and then Pragma_Name (Cond) = Name_Postcondition
995 Set_Ekind (Defining_Entity (Orig), Ekind (Gen_Id));
996 Prepend (New_Copy_Tree (Cond), Declarations (Orig));
1005 Analyze_Declarations (Declarations (N));
1007 Analyze (Handled_Statement_Sequence (N));
1009 Save_Global_References (Original_Node (N));
1011 -- Prior to exiting the scope, include generic formals again (if any
1012 -- are present) in the set of local entities.
1014 if Present (First_Ent) then
1015 Set_First_Entity (Gen_Id, First_Ent);
1018 Check_References (Gen_Id);
1021 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
1023 Check_Subprogram_Order (N);
1025 -- Outside of its body, unit is generic again
1027 Set_Ekind (Gen_Id, Kind);
1028 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
1031 Style.Check_Identifier (Body_Id, Gen_Id);
1035 end Analyze_Generic_Subprogram_Body;
1037 -----------------------------
1038 -- Analyze_Operator_Symbol --
1039 -----------------------------
1041 -- An operator symbol such as "+" or "and" may appear in context where the
1042 -- literal denotes an entity name, such as "+"(x, y) or in context when it
1043 -- is just a string, as in (conjunction = "or"). In these cases the parser
1044 -- generates this node, and the semantics does the disambiguation. Other
1045 -- such case are actuals in an instantiation, the generic unit in an
1046 -- instantiation, and pragma arguments.
1048 procedure Analyze_Operator_Symbol (N : Node_Id) is
1049 Par : constant Node_Id := Parent (N);
1052 if (Nkind (Par) = N_Function_Call
1053 and then N = Name (Par))
1054 or else Nkind (Par) = N_Function_Instantiation
1055 or else (Nkind (Par) = N_Indexed_Component
1056 and then N = Prefix (Par))
1057 or else (Nkind (Par) = N_Pragma_Argument_Association
1058 and then not Is_Pragma_String_Literal (Par))
1059 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
1060 or else (Nkind (Par) = N_Attribute_Reference
1061 and then Attribute_Name (Par) /= Name_Value)
1063 Find_Direct_Name (N);
1066 Change_Operator_Symbol_To_String_Literal (N);
1069 end Analyze_Operator_Symbol;
1071 -----------------------------------
1072 -- Analyze_Parameter_Association --
1073 -----------------------------------
1075 procedure Analyze_Parameter_Association (N : Node_Id) is
1077 Analyze (Explicit_Actual_Parameter (N));
1078 end Analyze_Parameter_Association;
1080 ----------------------------
1081 -- Analyze_Procedure_Call --
1082 ----------------------------
1084 procedure Analyze_Procedure_Call (N : Node_Id) is
1085 Loc : constant Source_Ptr := Sloc (N);
1086 P : constant Node_Id := Name (N);
1087 Actuals : constant List_Id := Parameter_Associations (N);
1091 procedure Analyze_Call_And_Resolve;
1092 -- Do Analyze and Resolve calls for procedure call
1093 -- At end, check illegal order dependence.
1095 ------------------------------
1096 -- Analyze_Call_And_Resolve --
1097 ------------------------------
1099 procedure Analyze_Call_And_Resolve is
1101 if Nkind (N) = N_Procedure_Call_Statement then
1103 Resolve (N, Standard_Void_Type);
1105 -- Apply checks suggested by AI05-0144
1107 Check_Order_Dependence;
1112 end Analyze_Call_And_Resolve;
1114 -- Start of processing for Analyze_Procedure_Call
1117 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
1118 -- a procedure call or an entry call. The prefix may denote an access
1119 -- to subprogram type, in which case an implicit dereference applies.
1120 -- If the prefix is an indexed component (without implicit dereference)
1121 -- then the construct denotes a call to a member of an entire family.
1122 -- If the prefix is a simple name, it may still denote a call to a
1123 -- parameterless member of an entry family. Resolution of these various
1124 -- interpretations is delicate.
1128 -- If this is a call of the form Obj.Op, the call may have been
1129 -- analyzed and possibly rewritten into a block, in which case
1132 if Analyzed (N) then
1136 -- If there is an error analyzing the name (which may have been
1137 -- rewritten if the original call was in prefix notation) then error
1138 -- has been emitted already, mark node and return.
1141 or else Etype (Name (N)) = Any_Type
1143 Set_Etype (N, Any_Type);
1147 -- Otherwise analyze the parameters
1149 if Present (Actuals) then
1150 Actual := First (Actuals);
1152 while Present (Actual) loop
1154 Check_Parameterless_Call (Actual);
1159 -- Special processing for Elab_Spec, Elab_Body and Elab_Subp_Body calls
1161 if Nkind (P) = N_Attribute_Reference
1162 and then (Attribute_Name (P) = Name_Elab_Spec
1163 or else Attribute_Name (P) = Name_Elab_Body
1164 or else Attribute_Name (P) = Name_Elab_Subp_Body)
1166 if Present (Actuals) then
1168 ("no parameters allowed for this call", First (Actuals));
1172 Set_Etype (N, Standard_Void_Type);
1175 elsif Is_Entity_Name (P)
1176 and then Is_Record_Type (Etype (Entity (P)))
1177 and then Remote_AST_I_Dereference (P)
1181 elsif Is_Entity_Name (P)
1182 and then Ekind (Entity (P)) /= E_Entry_Family
1184 if Is_Access_Type (Etype (P))
1185 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1186 and then No (Actuals)
1187 and then Comes_From_Source (N)
1189 Error_Msg_N ("missing explicit dereference in call", N);
1192 Analyze_Call_And_Resolve;
1194 -- If the prefix is the simple name of an entry family, this is
1195 -- a parameterless call from within the task body itself.
1197 elsif Is_Entity_Name (P)
1198 and then Nkind (P) = N_Identifier
1199 and then Ekind (Entity (P)) = E_Entry_Family
1200 and then Present (Actuals)
1201 and then No (Next (First (Actuals)))
1203 -- Can be call to parameterless entry family. What appears to be the
1204 -- sole argument is in fact the entry index. Rewrite prefix of node
1205 -- accordingly. Source representation is unchanged by this
1209 Make_Indexed_Component (Loc,
1211 Make_Selected_Component (Loc,
1212 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1213 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1214 Expressions => Actuals);
1215 Set_Name (N, New_N);
1216 Set_Etype (New_N, Standard_Void_Type);
1217 Set_Parameter_Associations (N, No_List);
1218 Analyze_Call_And_Resolve;
1220 elsif Nkind (P) = N_Explicit_Dereference then
1221 if Ekind (Etype (P)) = E_Subprogram_Type then
1222 Analyze_Call_And_Resolve;
1224 Error_Msg_N ("expect access to procedure in call", P);
1227 -- The name can be a selected component or an indexed component that
1228 -- yields an access to subprogram. Such a prefix is legal if the call
1229 -- has parameter associations.
1231 elsif Is_Access_Type (Etype (P))
1232 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1234 if Present (Actuals) then
1235 Analyze_Call_And_Resolve;
1237 Error_Msg_N ("missing explicit dereference in call ", N);
1240 -- If not an access to subprogram, then the prefix must resolve to the
1241 -- name of an entry, entry family, or protected operation.
1243 -- For the case of a simple entry call, P is a selected component where
1244 -- the prefix is the task and the selector name is the entry. A call to
1245 -- a protected procedure will have the same syntax. If the protected
1246 -- object contains overloaded operations, the entity may appear as a
1247 -- function, the context will select the operation whose type is Void.
1249 elsif Nkind (P) = N_Selected_Component
1250 and then (Ekind (Entity (Selector_Name (P))) = E_Entry
1252 Ekind (Entity (Selector_Name (P))) = E_Procedure
1254 Ekind (Entity (Selector_Name (P))) = E_Function)
1256 Analyze_Call_And_Resolve;
1258 elsif Nkind (P) = N_Selected_Component
1259 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1260 and then Present (Actuals)
1261 and then No (Next (First (Actuals)))
1263 -- Can be call to parameterless entry family. What appears to be the
1264 -- sole argument is in fact the entry index. Rewrite prefix of node
1265 -- accordingly. Source representation is unchanged by this
1269 Make_Indexed_Component (Loc,
1270 Prefix => New_Copy (P),
1271 Expressions => Actuals);
1272 Set_Name (N, New_N);
1273 Set_Etype (New_N, Standard_Void_Type);
1274 Set_Parameter_Associations (N, No_List);
1275 Analyze_Call_And_Resolve;
1277 -- For the case of a reference to an element of an entry family, P is
1278 -- an indexed component whose prefix is a selected component (task and
1279 -- entry family), and whose index is the entry family index.
1281 elsif Nkind (P) = N_Indexed_Component
1282 and then Nkind (Prefix (P)) = N_Selected_Component
1283 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
1285 Analyze_Call_And_Resolve;
1287 -- If the prefix is the name of an entry family, it is a call from
1288 -- within the task body itself.
1290 elsif Nkind (P) = N_Indexed_Component
1291 and then Nkind (Prefix (P)) = N_Identifier
1292 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
1295 Make_Selected_Component (Loc,
1296 Prefix => New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
1297 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
1298 Rewrite (Prefix (P), New_N);
1300 Analyze_Call_And_Resolve;
1302 -- Anything else is an error
1305 Error_Msg_N ("invalid procedure or entry call", N);
1307 end Analyze_Procedure_Call;
1309 ------------------------------
1310 -- Analyze_Return_Statement --
1311 ------------------------------
1313 procedure Analyze_Return_Statement (N : Node_Id) is
1315 pragma Assert (Nkind_In (N, N_Simple_Return_Statement,
1316 N_Extended_Return_Statement));
1318 Returns_Object : constant Boolean :=
1319 Nkind (N) = N_Extended_Return_Statement
1321 (Nkind (N) = N_Simple_Return_Statement
1322 and then Present (Expression (N)));
1323 -- True if we're returning something; that is, "return <expression>;"
1324 -- or "return Result : T [:= ...]". False for "return;". Used for error
1325 -- checking: If Returns_Object is True, N should apply to a function
1326 -- body; otherwise N should apply to a procedure body, entry body,
1327 -- accept statement, or extended return statement.
1329 function Find_What_It_Applies_To return Entity_Id;
1330 -- Find the entity representing the innermost enclosing body, accept
1331 -- statement, or extended return statement. If the result is a callable
1332 -- construct or extended return statement, then this will be the value
1333 -- of the Return_Applies_To attribute. Otherwise, the program is
1334 -- illegal. See RM-6.5(4/2).
1336 -----------------------------
1337 -- Find_What_It_Applies_To --
1338 -----------------------------
1340 function Find_What_It_Applies_To return Entity_Id is
1341 Result : Entity_Id := Empty;
1344 -- Loop outward through the Scope_Stack, skipping blocks and loops
1346 for J in reverse 0 .. Scope_Stack.Last loop
1347 Result := Scope_Stack.Table (J).Entity;
1348 exit when Ekind (Result) /= E_Block and then
1349 Ekind (Result) /= E_Loop;
1352 pragma Assert (Present (Result));
1354 end Find_What_It_Applies_To;
1356 -- Local declarations
1358 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
1359 Kind : constant Entity_Kind := Ekind (Scope_Id);
1360 Loc : constant Source_Ptr := Sloc (N);
1361 Stm_Entity : constant Entity_Id :=
1363 (E_Return_Statement, Current_Scope, Loc, 'R');
1365 -- Start of processing for Analyze_Return_Statement
1368 Set_Return_Statement_Entity (N, Stm_Entity);
1370 Set_Etype (Stm_Entity, Standard_Void_Type);
1371 Set_Return_Applies_To (Stm_Entity, Scope_Id);
1373 -- Place Return entity on scope stack, to simplify enforcement of 6.5
1374 -- (4/2): an inner return statement will apply to this extended return.
1376 if Nkind (N) = N_Extended_Return_Statement then
1377 Push_Scope (Stm_Entity);
1380 -- Check that pragma No_Return is obeyed. Don't complain about the
1381 -- implicitly-generated return that is placed at the end.
1383 if No_Return (Scope_Id) and then Comes_From_Source (N) then
1384 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
1387 -- Warn on any unassigned OUT parameters if in procedure
1389 if Ekind (Scope_Id) = E_Procedure then
1390 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
1393 -- Check that functions return objects, and other things do not
1395 if Kind = E_Function or else Kind = E_Generic_Function then
1396 if not Returns_Object then
1397 Error_Msg_N ("missing expression in return from function", N);
1400 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
1401 if Returns_Object then
1402 Error_Msg_N ("procedure cannot return value (use function)", N);
1405 elsif Kind = E_Entry or else Kind = E_Entry_Family then
1406 if Returns_Object then
1407 if Is_Protected_Type (Scope (Scope_Id)) then
1408 Error_Msg_N ("entry body cannot return value", N);
1410 Error_Msg_N ("accept statement cannot return value", N);
1414 elsif Kind = E_Return_Statement then
1416 -- We are nested within another return statement, which must be an
1417 -- extended_return_statement.
1419 if Returns_Object then
1421 ("extended_return_statement cannot return value; " &
1422 "use `""RETURN;""`", N);
1426 Error_Msg_N ("illegal context for return statement", N);
1429 if Ekind_In (Kind, E_Function, E_Generic_Function) then
1430 Analyze_Function_Return (N);
1432 elsif Ekind_In (Kind, E_Procedure, E_Generic_Procedure) then
1433 Set_Return_Present (Scope_Id);
1436 if Nkind (N) = N_Extended_Return_Statement then
1440 Kill_Current_Values (Last_Assignment_Only => True);
1441 Check_Unreachable_Code (N);
1442 end Analyze_Return_Statement;
1444 -------------------------------------
1445 -- Analyze_Simple_Return_Statement --
1446 -------------------------------------
1448 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
1450 if Present (Expression (N)) then
1451 Mark_Coextensions (N, Expression (N));
1454 Analyze_Return_Statement (N);
1455 end Analyze_Simple_Return_Statement;
1457 -------------------------
1458 -- Analyze_Return_Type --
1459 -------------------------
1461 procedure Analyze_Return_Type (N : Node_Id) is
1462 Designator : constant Entity_Id := Defining_Entity (N);
1463 Typ : Entity_Id := Empty;
1466 -- Normal case where result definition does not indicate an error
1468 if Result_Definition (N) /= Error then
1469 if Nkind (Result_Definition (N)) = N_Access_Definition then
1470 Check_SPARK_Restriction
1471 ("access result is not allowed", Result_Definition (N));
1473 -- Ada 2005 (AI-254): Handle anonymous access to subprograms
1476 AD : constant Node_Id :=
1477 Access_To_Subprogram_Definition (Result_Definition (N));
1479 if Present (AD) and then Protected_Present (AD) then
1480 Typ := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1482 Typ := Access_Definition (N, Result_Definition (N));
1486 Set_Parent (Typ, Result_Definition (N));
1487 Set_Is_Local_Anonymous_Access (Typ);
1488 Set_Etype (Designator, Typ);
1490 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
1492 Null_Exclusion_Static_Checks (N);
1494 -- Subtype_Mark case
1497 Find_Type (Result_Definition (N));
1498 Typ := Entity (Result_Definition (N));
1499 Set_Etype (Designator, Typ);
1501 -- Unconstrained array as result is not allowed in SPARK
1503 if Is_Array_Type (Typ)
1504 and then not Is_Constrained (Typ)
1506 Check_SPARK_Restriction
1507 ("returning an unconstrained array is not allowed",
1508 Result_Definition (N));
1511 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
1513 Null_Exclusion_Static_Checks (N);
1515 -- If a null exclusion is imposed on the result type, then create
1516 -- a null-excluding itype (an access subtype) and use it as the
1517 -- function's Etype. Note that the null exclusion checks are done
1518 -- right before this, because they don't get applied to types that
1519 -- do not come from source.
1521 if Is_Access_Type (Typ)
1522 and then Null_Exclusion_Present (N)
1524 Set_Etype (Designator,
1525 Create_Null_Excluding_Itype
1528 Scope_Id => Scope (Current_Scope)));
1530 -- The new subtype must be elaborated before use because
1531 -- it is visible outside of the function. However its base
1532 -- type may not be frozen yet, so the reference that will
1533 -- force elaboration must be attached to the freezing of
1536 -- If the return specification appears on a proper body,
1537 -- the subtype will have been created already on the spec.
1539 if Is_Frozen (Typ) then
1540 if Nkind (Parent (N)) = N_Subprogram_Body
1541 and then Nkind (Parent (Parent (N))) = N_Subunit
1545 Build_Itype_Reference (Etype (Designator), Parent (N));
1549 Ensure_Freeze_Node (Typ);
1552 IR : constant Node_Id := Make_Itype_Reference (Sloc (N));
1554 Set_Itype (IR, Etype (Designator));
1555 Append_Freeze_Actions (Typ, New_List (IR));
1560 Set_Etype (Designator, Typ);
1563 if Ekind (Typ) = E_Incomplete_Type
1564 and then Is_Value_Type (Typ)
1568 elsif Ekind (Typ) = E_Incomplete_Type
1569 or else (Is_Class_Wide_Type (Typ)
1571 Ekind (Root_Type (Typ)) = E_Incomplete_Type)
1573 -- AI05-0151: Tagged incomplete types are allowed in all formal
1574 -- parts. Untagged incomplete types are not allowed in bodies.
1576 if Ada_Version >= Ada_2012 then
1577 if Is_Tagged_Type (Typ) then
1580 elsif Nkind_In (Parent (Parent (N)),
1586 ("invalid use of untagged incomplete type&",
1592 ("invalid use of incomplete type&", Designator, Typ);
1597 -- Case where result definition does indicate an error
1600 Set_Etype (Designator, Any_Type);
1602 end Analyze_Return_Type;
1604 -----------------------------
1605 -- Analyze_Subprogram_Body --
1606 -----------------------------
1608 procedure Analyze_Subprogram_Body (N : Node_Id) is
1609 Loc : constant Source_Ptr := Sloc (N);
1610 Body_Spec : constant Node_Id := Specification (N);
1611 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
1614 if Debug_Flag_C then
1615 Write_Str ("==> subprogram body ");
1616 Write_Name (Chars (Body_Id));
1617 Write_Str (" from ");
1618 Write_Location (Loc);
1623 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
1625 -- The real work is split out into the helper, so it can do "return;"
1626 -- without skipping the debug output:
1628 Analyze_Subprogram_Body_Helper (N);
1630 if Debug_Flag_C then
1632 Write_Str ("<== subprogram body ");
1633 Write_Name (Chars (Body_Id));
1634 Write_Str (" from ");
1635 Write_Location (Loc);
1638 end Analyze_Subprogram_Body;
1640 ------------------------------------
1641 -- Analyze_Subprogram_Body_Helper --
1642 ------------------------------------
1644 -- This procedure is called for regular subprogram bodies, generic bodies,
1645 -- and for subprogram stubs of both kinds. In the case of stubs, only the
1646 -- specification matters, and is used to create a proper declaration for
1647 -- the subprogram, or to perform conformance checks.
1649 procedure Analyze_Subprogram_Body_Helper (N : Node_Id) is
1650 Loc : constant Source_Ptr := Sloc (N);
1651 Body_Deleted : constant Boolean := False;
1652 Body_Spec : constant Node_Id := Specification (N);
1653 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
1654 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
1655 Conformant : Boolean;
1658 Prot_Typ : Entity_Id := Empty;
1659 Spec_Id : Entity_Id;
1660 Spec_Decl : Node_Id := Empty;
1662 Last_Real_Spec_Entity : Entity_Id := Empty;
1663 -- When we analyze a separate spec, the entity chain ends up containing
1664 -- the formals, as well as any itypes generated during analysis of the
1665 -- default expressions for parameters, or the arguments of associated
1666 -- precondition/postcondition pragmas (which are analyzed in the context
1667 -- of the spec since they have visibility on formals).
1669 -- These entities belong with the spec and not the body. However we do
1670 -- the analysis of the body in the context of the spec (again to obtain
1671 -- visibility to the formals), and all the entities generated during
1672 -- this analysis end up also chained to the entity chain of the spec.
1673 -- But they really belong to the body, and there is circuitry to move
1674 -- them from the spec to the body.
1676 -- However, when we do this move, we don't want to move the real spec
1677 -- entities (first para above) to the body. The Last_Real_Spec_Entity
1678 -- variable points to the last real spec entity, so we only move those
1679 -- chained beyond that point. It is initialized to Empty to deal with
1680 -- the case where there is no separate spec.
1682 procedure Check_Anonymous_Return;
1683 -- Ada 2005: if a function returns an access type that denotes a task,
1684 -- or a type that contains tasks, we must create a master entity for
1685 -- the anonymous type, which typically will be used in an allocator
1686 -- in the body of the function.
1688 procedure Check_Inline_Pragma (Spec : in out Node_Id);
1689 -- Look ahead to recognize a pragma that may appear after the body.
1690 -- If there is a previous spec, check that it appears in the same
1691 -- declarative part. If the pragma is Inline_Always, perform inlining
1692 -- unconditionally, otherwise only if Front_End_Inlining is requested.
1693 -- If the body acts as a spec, and inlining is required, we create a
1694 -- subprogram declaration for it, in order to attach the body to inline.
1695 -- If pragma does not appear after the body, check whether there is
1696 -- an inline pragma before any local declarations.
1698 procedure Check_Missing_Return;
1699 -- Checks for a function with a no return statements, and also performs
1700 -- the warning checks implemented by Check_Returns. In formal mode, also
1701 -- verify that a function ends with a RETURN and that a procedure does
1702 -- not contain any RETURN.
1704 function Disambiguate_Spec return Entity_Id;
1705 -- When a primitive is declared between the private view and the full
1706 -- view of a concurrent type which implements an interface, a special
1707 -- mechanism is used to find the corresponding spec of the primitive
1710 function Is_Private_Concurrent_Primitive
1711 (Subp_Id : Entity_Id) return Boolean;
1712 -- Determine whether subprogram Subp_Id is a primitive of a concurrent
1713 -- type that implements an interface and has a private view.
1715 procedure Set_Trivial_Subprogram (N : Node_Id);
1716 -- Sets the Is_Trivial_Subprogram flag in both spec and body of the
1717 -- subprogram whose body is being analyzed. N is the statement node
1718 -- causing the flag to be set, if the following statement is a return
1719 -- of an entity, we mark the entity as set in source to suppress any
1720 -- warning on the stylized use of function stubs with a dummy return.
1722 procedure Verify_Overriding_Indicator;
1723 -- If there was a previous spec, the entity has been entered in the
1724 -- current scope previously. If the body itself carries an overriding
1725 -- indicator, check that it is consistent with the known status of the
1728 ----------------------------
1729 -- Check_Anonymous_Return --
1730 ----------------------------
1732 procedure Check_Anonymous_Return is
1738 if Present (Spec_Id) then
1744 if Ekind (Scop) = E_Function
1745 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
1746 and then not Is_Thunk (Scop)
1747 and then (Has_Task (Designated_Type (Etype (Scop)))
1749 (Is_Class_Wide_Type (Designated_Type (Etype (Scop)))
1751 Is_Limited_Record (Designated_Type (Etype (Scop)))))
1752 and then Expander_Active
1754 -- Avoid cases with no tasking support
1756 and then RTE_Available (RE_Current_Master)
1757 and then not Restriction_Active (No_Task_Hierarchy)
1760 Make_Object_Declaration (Loc,
1761 Defining_Identifier =>
1762 Make_Defining_Identifier (Loc, Name_uMaster),
1763 Constant_Present => True,
1764 Object_Definition =>
1765 New_Reference_To (RTE (RE_Master_Id), Loc),
1767 Make_Explicit_Dereference (Loc,
1768 New_Reference_To (RTE (RE_Current_Master), Loc)));
1770 if Present (Declarations (N)) then
1771 Prepend (Decl, Declarations (N));
1773 Set_Declarations (N, New_List (Decl));
1776 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
1777 Set_Has_Master_Entity (Scop);
1779 -- Now mark the containing scope as a task master
1782 while Nkind (Par) /= N_Compilation_Unit loop
1783 Par := Parent (Par);
1784 pragma Assert (Present (Par));
1786 -- If we fall off the top, we are at the outer level, and
1787 -- the environment task is our effective master, so nothing
1791 (Par, N_Task_Body, N_Block_Statement, N_Subprogram_Body)
1793 Set_Is_Task_Master (Par, True);
1798 end Check_Anonymous_Return;
1800 -------------------------
1801 -- Check_Inline_Pragma --
1802 -------------------------
1804 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
1808 function Is_Inline_Pragma (N : Node_Id) return Boolean;
1809 -- True when N is a pragma Inline or Inline_Always that applies
1810 -- to this subprogram.
1812 -----------------------
1813 -- Is_Inline_Pragma --
1814 -----------------------
1816 function Is_Inline_Pragma (N : Node_Id) return Boolean is
1819 Nkind (N) = N_Pragma
1821 (Pragma_Name (N) = Name_Inline_Always
1824 and then Pragma_Name (N) = Name_Inline))
1827 (Expression (First (Pragma_Argument_Associations (N))))
1829 end Is_Inline_Pragma;
1831 -- Start of processing for Check_Inline_Pragma
1834 if not Expander_Active then
1838 if Is_List_Member (N)
1839 and then Present (Next (N))
1840 and then Is_Inline_Pragma (Next (N))
1844 elsif Nkind (N) /= N_Subprogram_Body_Stub
1845 and then Present (Declarations (N))
1846 and then Is_Inline_Pragma (First (Declarations (N)))
1848 Prag := First (Declarations (N));
1854 if Present (Prag) then
1855 if Present (Spec_Id) then
1856 if In_Same_List (N, Unit_Declaration_Node (Spec_Id)) then
1861 -- Create a subprogram declaration, to make treatment uniform
1864 Subp : constant Entity_Id :=
1865 Make_Defining_Identifier (Loc, Chars (Body_Id));
1866 Decl : constant Node_Id :=
1867 Make_Subprogram_Declaration (Loc,
1869 New_Copy_Tree (Specification (N)));
1872 Set_Defining_Unit_Name (Specification (Decl), Subp);
1874 if Present (First_Formal (Body_Id)) then
1875 Plist := Copy_Parameter_List (Body_Id);
1876 Set_Parameter_Specifications
1877 (Specification (Decl), Plist);
1880 Insert_Before (N, Decl);
1883 Set_Has_Pragma_Inline (Subp);
1885 if Pragma_Name (Prag) = Name_Inline_Always then
1886 Set_Is_Inlined (Subp);
1887 Set_Has_Pragma_Inline_Always (Subp);
1894 end Check_Inline_Pragma;
1896 --------------------------
1897 -- Check_Missing_Return --
1898 --------------------------
1900 procedure Check_Missing_Return is
1902 Missing_Ret : Boolean;
1905 if Nkind (Body_Spec) = N_Function_Specification then
1906 if Present (Spec_Id) then
1912 if Return_Present (Id) then
1913 Check_Returns (HSS, 'F', Missing_Ret);
1916 Set_Has_Missing_Return (Id);
1919 elsif (Is_Generic_Subprogram (Id)
1920 or else not Is_Machine_Code_Subprogram (Id))
1921 and then not Body_Deleted
1923 Error_Msg_N ("missing RETURN statement in function body", N);
1926 -- If procedure with No_Return, check returns
1928 elsif Nkind (Body_Spec) = N_Procedure_Specification
1929 and then Present (Spec_Id)
1930 and then No_Return (Spec_Id)
1932 Check_Returns (HSS, 'P', Missing_Ret, Spec_Id);
1935 -- Special checks in SPARK mode
1937 if Nkind (Body_Spec) = N_Function_Specification then
1939 -- In SPARK mode, last statement of a function should be a return
1942 Stat : constant Node_Id := Last_Source_Statement (HSS);
1945 and then not Nkind_In (Stat, N_Simple_Return_Statement,
1946 N_Extended_Return_Statement)
1948 Check_SPARK_Restriction
1949 ("last statement in function should be RETURN", Stat);
1953 -- In SPARK mode, verify that a procedure has no return
1955 elsif Nkind (Body_Spec) = N_Procedure_Specification then
1956 if Present (Spec_Id) then
1962 -- Would be nice to point to return statement here, can we
1963 -- borrow the Check_Returns procedure here ???
1965 if Return_Present (Id) then
1966 Check_SPARK_Restriction
1967 ("procedure should not have RETURN", N);
1970 end Check_Missing_Return;
1972 -----------------------
1973 -- Disambiguate_Spec --
1974 -----------------------
1976 function Disambiguate_Spec return Entity_Id is
1977 Priv_Spec : Entity_Id;
1980 procedure Replace_Types (To_Corresponding : Boolean);
1981 -- Depending on the flag, replace the type of formal parameters of
1982 -- Body_Id if it is a concurrent type implementing interfaces with
1983 -- the corresponding record type or the other way around.
1985 procedure Replace_Types (To_Corresponding : Boolean) is
1987 Formal_Typ : Entity_Id;
1990 Formal := First_Formal (Body_Id);
1991 while Present (Formal) loop
1992 Formal_Typ := Etype (Formal);
1994 if Is_Class_Wide_Type (Formal_Typ) then
1995 Formal_Typ := Root_Type (Formal_Typ);
1998 -- From concurrent type to corresponding record
2000 if To_Corresponding then
2001 if Is_Concurrent_Type (Formal_Typ)
2002 and then Present (Corresponding_Record_Type (Formal_Typ))
2003 and then Present (Interfaces (
2004 Corresponding_Record_Type (Formal_Typ)))
2007 Corresponding_Record_Type (Formal_Typ));
2010 -- From corresponding record to concurrent type
2013 if Is_Concurrent_Record_Type (Formal_Typ)
2014 and then Present (Interfaces (Formal_Typ))
2017 Corresponding_Concurrent_Type (Formal_Typ));
2021 Next_Formal (Formal);
2025 -- Start of processing for Disambiguate_Spec
2028 -- Try to retrieve the specification of the body as is. All error
2029 -- messages are suppressed because the body may not have a spec in
2030 -- its current state.
2032 Spec_N := Find_Corresponding_Spec (N, False);
2034 -- It is possible that this is the body of a primitive declared
2035 -- between a private and a full view of a concurrent type. The
2036 -- controlling parameter of the spec carries the concurrent type,
2037 -- not the corresponding record type as transformed by Analyze_
2038 -- Subprogram_Specification. In such cases, we undo the change
2039 -- made by the analysis of the specification and try to find the
2042 -- Note that wrappers already have their corresponding specs and
2043 -- bodies set during their creation, so if the candidate spec is
2044 -- a wrapper, then we definitely need to swap all types to their
2045 -- original concurrent status.
2048 or else Is_Primitive_Wrapper (Spec_N)
2050 -- Restore all references of corresponding record types to the
2051 -- original concurrent types.
2053 Replace_Types (To_Corresponding => False);
2054 Priv_Spec := Find_Corresponding_Spec (N, False);
2056 -- The current body truly belongs to a primitive declared between
2057 -- a private and a full view. We leave the modified body as is,
2058 -- and return the true spec.
2060 if Present (Priv_Spec)
2061 and then Is_Private_Primitive (Priv_Spec)
2066 -- In case that this is some sort of error, restore the original
2067 -- state of the body.
2069 Replace_Types (To_Corresponding => True);
2073 end Disambiguate_Spec;
2075 -------------------------------------
2076 -- Is_Private_Concurrent_Primitive --
2077 -------------------------------------
2079 function Is_Private_Concurrent_Primitive
2080 (Subp_Id : Entity_Id) return Boolean
2082 Formal_Typ : Entity_Id;
2085 if Present (First_Formal (Subp_Id)) then
2086 Formal_Typ := Etype (First_Formal (Subp_Id));
2088 if Is_Concurrent_Record_Type (Formal_Typ) then
2089 if Is_Class_Wide_Type (Formal_Typ) then
2090 Formal_Typ := Root_Type (Formal_Typ);
2093 Formal_Typ := Corresponding_Concurrent_Type (Formal_Typ);
2096 -- The type of the first formal is a concurrent tagged type with
2100 Is_Concurrent_Type (Formal_Typ)
2101 and then Is_Tagged_Type (Formal_Typ)
2102 and then Has_Private_Declaration (Formal_Typ);
2106 end Is_Private_Concurrent_Primitive;
2108 ----------------------------
2109 -- Set_Trivial_Subprogram --
2110 ----------------------------
2112 procedure Set_Trivial_Subprogram (N : Node_Id) is
2113 Nxt : constant Node_Id := Next (N);
2116 Set_Is_Trivial_Subprogram (Body_Id);
2118 if Present (Spec_Id) then
2119 Set_Is_Trivial_Subprogram (Spec_Id);
2123 and then Nkind (Nxt) = N_Simple_Return_Statement
2124 and then No (Next (Nxt))
2125 and then Present (Expression (Nxt))
2126 and then Is_Entity_Name (Expression (Nxt))
2128 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
2130 end Set_Trivial_Subprogram;
2132 ---------------------------------
2133 -- Verify_Overriding_Indicator --
2134 ---------------------------------
2136 procedure Verify_Overriding_Indicator is
2138 if Must_Override (Body_Spec) then
2139 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
2140 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
2144 elsif not Present (Overridden_Operation (Spec_Id)) then
2146 ("subprogram& is not overriding", Body_Spec, Spec_Id);
2149 elsif Must_Not_Override (Body_Spec) then
2150 if Present (Overridden_Operation (Spec_Id)) then
2152 ("subprogram& overrides inherited operation",
2153 Body_Spec, Spec_Id);
2155 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
2156 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
2159 ("subprogram & overrides predefined operator ",
2160 Body_Spec, Spec_Id);
2162 -- If this is not a primitive operation or protected subprogram,
2163 -- then the overriding indicator is altogether illegal.
2165 elsif not Is_Primitive (Spec_Id)
2166 and then Ekind (Scope (Spec_Id)) /= E_Protected_Type
2169 ("overriding indicator only allowed " &
2170 "if subprogram is primitive",
2175 and then Present (Overridden_Operation (Spec_Id))
2177 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
2178 Style.Missing_Overriding (N, Body_Id);
2181 and then Can_Override_Operator (Spec_Id)
2182 and then not Is_Predefined_File_Name
2183 (Unit_File_Name (Get_Source_Unit (Spec_Id)))
2185 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
2186 Style.Missing_Overriding (N, Body_Id);
2188 end Verify_Overriding_Indicator;
2190 -- Start of processing for Analyze_Subprogram_Body_Helper
2193 -- Generic subprograms are handled separately. They always have a
2194 -- generic specification. Determine whether current scope has a
2195 -- previous declaration.
2197 -- If the subprogram body is defined within an instance of the same
2198 -- name, the instance appears as a package renaming, and will be hidden
2199 -- within the subprogram.
2201 if Present (Prev_Id)
2202 and then not Is_Overloadable (Prev_Id)
2203 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
2204 or else Comes_From_Source (Prev_Id))
2206 if Is_Generic_Subprogram (Prev_Id) then
2208 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
2209 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
2211 Analyze_Generic_Subprogram_Body (N, Spec_Id);
2213 if Nkind (N) = N_Subprogram_Body then
2214 HSS := Handled_Statement_Sequence (N);
2215 Check_Missing_Return;
2221 -- Previous entity conflicts with subprogram name. Attempting to
2222 -- enter name will post error.
2224 Enter_Name (Body_Id);
2228 -- Non-generic case, find the subprogram declaration, if one was seen,
2229 -- or enter new overloaded entity in the current scope. If the
2230 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
2231 -- part of the context of one of its subunits. No need to redo the
2234 elsif Prev_Id = Body_Id
2235 and then Has_Completion (Body_Id)
2240 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
2242 if Nkind (N) = N_Subprogram_Body_Stub
2243 or else No (Corresponding_Spec (N))
2245 if Is_Private_Concurrent_Primitive (Body_Id) then
2246 Spec_Id := Disambiguate_Spec;
2248 Spec_Id := Find_Corresponding_Spec (N);
2251 -- If this is a duplicate body, no point in analyzing it
2253 if Error_Posted (N) then
2257 -- A subprogram body should cause freezing of its own declaration,
2258 -- but if there was no previous explicit declaration, then the
2259 -- subprogram will get frozen too late (there may be code within
2260 -- the body that depends on the subprogram having been frozen,
2261 -- such as uses of extra formals), so we force it to be frozen
2262 -- here. Same holds if the body and spec are compilation units.
2263 -- Finally, if the return type is an anonymous access to protected
2264 -- subprogram, it must be frozen before the body because its
2265 -- expansion has generated an equivalent type that is used when
2266 -- elaborating the body.
2268 if No (Spec_Id) then
2269 Freeze_Before (N, Body_Id);
2271 elsif Nkind (Parent (N)) = N_Compilation_Unit then
2272 Freeze_Before (N, Spec_Id);
2274 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
2275 Freeze_Before (N, Etype (Body_Id));
2279 Spec_Id := Corresponding_Spec (N);
2283 -- Do not inline any subprogram that contains nested subprograms, since
2284 -- the backend inlining circuit seems to generate uninitialized
2285 -- references in this case. We know this happens in the case of front
2286 -- end ZCX support, but it also appears it can happen in other cases as
2287 -- well. The backend often rejects attempts to inline in the case of
2288 -- nested procedures anyway, so little if anything is lost by this.
2289 -- Note that this is test is for the benefit of the back-end. There is
2290 -- a separate test for front-end inlining that also rejects nested
2293 -- Do not do this test if errors have been detected, because in some
2294 -- error cases, this code blows up, and we don't need it anyway if
2295 -- there have been errors, since we won't get to the linker anyway.
2297 if Comes_From_Source (Body_Id)
2298 and then Serious_Errors_Detected = 0
2302 P_Ent := Scope (P_Ent);
2303 exit when No (P_Ent) or else P_Ent = Standard_Standard;
2305 if Is_Subprogram (P_Ent) then
2306 Set_Is_Inlined (P_Ent, False);
2308 if Comes_From_Source (P_Ent)
2309 and then Has_Pragma_Inline (P_Ent)
2312 ("cannot inline& (nested subprogram)?",
2319 Check_Inline_Pragma (Spec_Id);
2321 -- Deal with special case of a fully private operation in the body of
2322 -- the protected type. We must create a declaration for the subprogram,
2323 -- in order to attach the protected subprogram that will be used in
2324 -- internal calls. We exclude compiler generated bodies from the
2325 -- expander since the issue does not arise for those cases.
2328 and then Comes_From_Source (N)
2329 and then Is_Protected_Type (Current_Scope)
2331 Spec_Id := Build_Private_Protected_Declaration (N);
2334 -- If a separate spec is present, then deal with freezing issues
2336 if Present (Spec_Id) then
2337 Spec_Decl := Unit_Declaration_Node (Spec_Id);
2338 Verify_Overriding_Indicator;
2340 -- In general, the spec will be frozen when we start analyzing the
2341 -- body. However, for internally generated operations, such as
2342 -- wrapper functions for inherited operations with controlling
2343 -- results, the spec may not have been frozen by the time we
2344 -- expand the freeze actions that include the bodies. In particular,
2345 -- extra formals for accessibility or for return-in-place may need
2346 -- to be generated. Freeze nodes, if any, are inserted before the
2349 if not Is_Frozen (Spec_Id)
2350 and then Expander_Active
2352 -- Force the generation of its freezing node to ensure proper
2353 -- management of access types in the backend.
2355 -- This is definitely needed for some cases, but it is not clear
2356 -- why, to be investigated further???
2358 Set_Has_Delayed_Freeze (Spec_Id);
2359 Freeze_Before (N, Spec_Id);
2363 -- Mark presence of postcondition procedure in current scope and mark
2364 -- the procedure itself as needing debug info. The latter is important
2365 -- when analyzing decision coverage (for example, for MC/DC coverage).
2367 if Chars (Body_Id) = Name_uPostconditions then
2368 Set_Has_Postconditions (Current_Scope);
2369 Set_Debug_Info_Needed (Body_Id);
2372 -- Place subprogram on scope stack, and make formals visible. If there
2373 -- is a spec, the visible entity remains that of the spec.
2375 if Present (Spec_Id) then
2376 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
2378 if Is_Child_Unit (Spec_Id) then
2379 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
2383 Style.Check_Identifier (Body_Id, Spec_Id);
2386 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
2387 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
2389 if Is_Abstract_Subprogram (Spec_Id) then
2390 Error_Msg_N ("an abstract subprogram cannot have a body", N);
2394 Set_Convention (Body_Id, Convention (Spec_Id));
2395 Set_Has_Completion (Spec_Id);
2397 if Is_Protected_Type (Scope (Spec_Id)) then
2398 Prot_Typ := Scope (Spec_Id);
2401 -- If this is a body generated for a renaming, do not check for
2402 -- full conformance. The check is redundant, because the spec of
2403 -- the body is a copy of the spec in the renaming declaration,
2404 -- and the test can lead to spurious errors on nested defaults.
2406 if Present (Spec_Decl)
2407 and then not Comes_From_Source (N)
2409 (Nkind (Original_Node (Spec_Decl)) =
2410 N_Subprogram_Renaming_Declaration
2411 or else (Present (Corresponding_Body (Spec_Decl))
2413 Nkind (Unit_Declaration_Node
2414 (Corresponding_Body (Spec_Decl))) =
2415 N_Subprogram_Renaming_Declaration))
2419 -- Conversely, the spec may have been generated for specless body
2420 -- with an inline pragma.
2422 elsif Comes_From_Source (N)
2423 and then not Comes_From_Source (Spec_Id)
2424 and then Has_Pragma_Inline (Spec_Id)
2431 Fully_Conformant, True, Conformant, Body_Id);
2434 -- If the body is not fully conformant, we have to decide if we
2435 -- should analyze it or not. If it has a really messed up profile
2436 -- then we probably should not analyze it, since we will get too
2437 -- many bogus messages.
2439 -- Our decision is to go ahead in the non-fully conformant case
2440 -- only if it is at least mode conformant with the spec. Note
2441 -- that the call to Check_Fully_Conformant has issued the proper
2442 -- error messages to complain about the lack of conformance.
2445 and then not Mode_Conformant (Body_Id, Spec_Id)
2451 if Spec_Id /= Body_Id then
2452 Reference_Body_Formals (Spec_Id, Body_Id);
2455 if Nkind (N) /= N_Subprogram_Body_Stub then
2456 Set_Corresponding_Spec (N, Spec_Id);
2458 -- Ada 2005 (AI-345): If the operation is a primitive operation
2459 -- of a concurrent type, the type of the first parameter has been
2460 -- replaced with the corresponding record, which is the proper
2461 -- run-time structure to use. However, within the body there may
2462 -- be uses of the formals that depend on primitive operations
2463 -- of the type (in particular calls in prefixed form) for which
2464 -- we need the original concurrent type. The operation may have
2465 -- several controlling formals, so the replacement must be done
2468 if Comes_From_Source (Spec_Id)
2469 and then Present (First_Entity (Spec_Id))
2470 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
2471 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
2473 Present (Interfaces (Etype (First_Entity (Spec_Id))))
2476 (Corresponding_Concurrent_Type
2477 (Etype (First_Entity (Spec_Id))))
2480 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
2484 Form := First_Formal (Spec_Id);
2485 while Present (Form) loop
2486 if Etype (Form) = Typ then
2487 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
2495 -- Make the formals visible, and place subprogram on scope stack.
2496 -- This is also the point at which we set Last_Real_Spec_Entity
2497 -- to mark the entities which will not be moved to the body.
2499 Install_Formals (Spec_Id);
2500 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
2501 Push_Scope (Spec_Id);
2503 -- Make sure that the subprogram is immediately visible. For
2504 -- child units that have no separate spec this is indispensable.
2505 -- Otherwise it is safe albeit redundant.
2507 Set_Is_Immediately_Visible (Spec_Id);
2510 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
2511 Set_Ekind (Body_Id, E_Subprogram_Body);
2512 Set_Scope (Body_Id, Scope (Spec_Id));
2513 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
2515 -- Case of subprogram body with no previous spec
2518 -- Check for style warning required
2522 -- Only apply check for source level subprograms for which checks
2523 -- have not been suppressed.
2525 and then Comes_From_Source (Body_Id)
2526 and then not Suppress_Style_Checks (Body_Id)
2528 -- No warnings within an instance
2530 and then not In_Instance
2532 -- No warnings for expression functions
2534 and then Nkind (Original_Node (N)) /= N_Expression_Function
2536 Style.Body_With_No_Spec (N);
2539 New_Overloaded_Entity (Body_Id);
2541 if Nkind (N) /= N_Subprogram_Body_Stub then
2542 Set_Acts_As_Spec (N);
2543 Generate_Definition (Body_Id);
2544 Set_Contract (Body_Id, Make_Contract (Sloc (Body_Id)));
2546 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
2547 Generate_Reference_To_Formals (Body_Id);
2548 Install_Formals (Body_Id);
2549 Push_Scope (Body_Id);
2553 -- If the return type is an anonymous access type whose designated type
2554 -- is the limited view of a class-wide type and the non-limited view is
2555 -- available, update the return type accordingly.
2557 if Ada_Version >= Ada_2005
2558 and then Comes_From_Source (N)
2565 Rtyp := Etype (Current_Scope);
2567 if Ekind (Rtyp) = E_Anonymous_Access_Type then
2568 Etyp := Directly_Designated_Type (Rtyp);
2570 if Is_Class_Wide_Type (Etyp)
2571 and then From_With_Type (Etyp)
2573 Set_Directly_Designated_Type
2574 (Etype (Current_Scope), Available_View (Etyp));
2580 -- If this is the proper body of a stub, we must verify that the stub
2581 -- conforms to the body, and to the previous spec if one was present.
2582 -- we know already that the body conforms to that spec. This test is
2583 -- only required for subprograms that come from source.
2585 if Nkind (Parent (N)) = N_Subunit
2586 and then Comes_From_Source (N)
2587 and then not Error_Posted (Body_Id)
2588 and then Nkind (Corresponding_Stub (Parent (N))) =
2589 N_Subprogram_Body_Stub
2592 Old_Id : constant Entity_Id :=
2594 (Specification (Corresponding_Stub (Parent (N))));
2596 Conformant : Boolean := False;
2599 if No (Spec_Id) then
2600 Check_Fully_Conformant (Body_Id, Old_Id);
2604 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
2606 if not Conformant then
2608 -- The stub was taken to be a new declaration. Indicate
2609 -- that it lacks a body.
2611 Set_Has_Completion (Old_Id, False);
2617 Set_Has_Completion (Body_Id);
2618 Check_Eliminated (Body_Id);
2620 if Nkind (N) = N_Subprogram_Body_Stub then
2623 elsif Present (Spec_Id)
2624 and then Expander_Active
2626 (Has_Pragma_Inline_Always (Spec_Id)
2627 or else (Has_Pragma_Inline (Spec_Id) and Front_End_Inlining))
2629 Build_Body_To_Inline (N, Spec_Id);
2632 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
2633 -- if its specification we have to install the private withed units.
2634 -- This holds for child units as well.
2636 if Is_Compilation_Unit (Body_Id)
2637 or else Nkind (Parent (N)) = N_Compilation_Unit
2639 Install_Private_With_Clauses (Body_Id);
2642 Check_Anonymous_Return;
2644 -- Set the Protected_Formal field of each extra formal of the protected
2645 -- subprogram to reference the corresponding extra formal of the
2646 -- subprogram that implements it. For regular formals this occurs when
2647 -- the protected subprogram's declaration is expanded, but the extra
2648 -- formals don't get created until the subprogram is frozen. We need to
2649 -- do this before analyzing the protected subprogram's body so that any
2650 -- references to the original subprogram's extra formals will be changed
2651 -- refer to the implementing subprogram's formals (see Expand_Formal).
2653 if Present (Spec_Id)
2654 and then Is_Protected_Type (Scope (Spec_Id))
2655 and then Present (Protected_Body_Subprogram (Spec_Id))
2658 Impl_Subp : constant Entity_Id :=
2659 Protected_Body_Subprogram (Spec_Id);
2660 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
2661 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
2663 while Present (Prot_Ext_Formal) loop
2664 pragma Assert (Present (Impl_Ext_Formal));
2665 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
2666 Next_Formal_With_Extras (Prot_Ext_Formal);
2667 Next_Formal_With_Extras (Impl_Ext_Formal);
2672 -- Now we can go on to analyze the body
2674 HSS := Handled_Statement_Sequence (N);
2675 Set_Actual_Subtypes (N, Current_Scope);
2677 -- Deal with preconditions and postconditions. In formal verification
2678 -- mode, we keep pre- and postconditions attached to entities rather
2679 -- than inserted in the code, in order to facilitate a distinct
2680 -- treatment for them.
2682 if not ALFA_Mode then
2683 Process_PPCs (N, Spec_Id, Body_Id);
2686 -- Add a declaration for the Protection object, renaming declarations
2687 -- for discriminals and privals and finally a declaration for the entry
2688 -- family index (if applicable). This form of early expansion is done
2689 -- when the Expander is active because Install_Private_Data_Declarations
2690 -- references entities which were created during regular expansion.
2693 and then Comes_From_Source (N)
2694 and then Present (Prot_Typ)
2695 and then Present (Spec_Id)
2696 and then not Is_Eliminated (Spec_Id)
2698 Install_Private_Data_Declarations
2699 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
2702 -- Analyze the declarations (this call will analyze the precondition
2703 -- Check pragmas we prepended to the list, as well as the declaration
2704 -- of the _Postconditions procedure).
2706 Analyze_Declarations (Declarations (N));
2708 -- Check completion, and analyze the statements
2711 Inspect_Deferred_Constant_Completion (Declarations (N));
2714 -- Deal with end of scope processing for the body
2716 Process_End_Label (HSS, 't', Current_Scope);
2718 Check_Subprogram_Order (N);
2719 Set_Analyzed (Body_Id);
2721 -- If we have a separate spec, then the analysis of the declarations
2722 -- caused the entities in the body to be chained to the spec id, but
2723 -- we want them chained to the body id. Only the formal parameters
2724 -- end up chained to the spec id in this case.
2726 if Present (Spec_Id) then
2728 -- We must conform to the categorization of our spec
2730 Validate_Categorization_Dependency (N, Spec_Id);
2732 -- And if this is a child unit, the parent units must conform
2734 if Is_Child_Unit (Spec_Id) then
2735 Validate_Categorization_Dependency
2736 (Unit_Declaration_Node (Spec_Id), Spec_Id);
2739 -- Here is where we move entities from the spec to the body
2741 -- Case where there are entities that stay with the spec
2743 if Present (Last_Real_Spec_Entity) then
2745 -- No body entities (happens when the only real spec entities
2746 -- come from precondition and postcondition pragmas)
2748 if No (Last_Entity (Body_Id)) then
2750 (Body_Id, Next_Entity (Last_Real_Spec_Entity));
2752 -- Body entities present (formals), so chain stuff past them
2756 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
2759 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
2760 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
2761 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
2763 -- Case where there are no spec entities, in this case there can
2764 -- be no body entities either, so just move everything.
2767 pragma Assert (No (Last_Entity (Body_Id)));
2768 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
2769 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
2770 Set_First_Entity (Spec_Id, Empty);
2771 Set_Last_Entity (Spec_Id, Empty);
2775 Check_Missing_Return;
2777 -- Now we are going to check for variables that are never modified in
2778 -- the body of the procedure. But first we deal with a special case
2779 -- where we want to modify this check. If the body of the subprogram
2780 -- starts with a raise statement or its equivalent, or if the body
2781 -- consists entirely of a null statement, then it is pretty obvious
2782 -- that it is OK to not reference the parameters. For example, this
2783 -- might be the following common idiom for a stubbed function:
2784 -- statement of the procedure raises an exception. In particular this
2785 -- deals with the common idiom of a stubbed function, which might
2786 -- appear as something like
2788 -- function F (A : Integer) return Some_Type;
2791 -- raise Program_Error;
2795 -- Here the purpose of X is simply to satisfy the annoying requirement
2796 -- in Ada that there be at least one return, and we certainly do not
2797 -- want to go posting warnings on X that it is not initialized! On
2798 -- the other hand, if X is entirely unreferenced that should still
2801 -- What we do is to detect these cases, and if we find them, flag the
2802 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
2803 -- suppress unwanted warnings. For the case of the function stub above
2804 -- we have a special test to set X as apparently assigned to suppress
2811 -- Skip initial labels (for one thing this occurs when we are in
2812 -- front end ZCX mode, but in any case it is irrelevant), and also
2813 -- initial Push_xxx_Error_Label nodes, which are also irrelevant.
2815 Stm := First (Statements (HSS));
2816 while Nkind (Stm) = N_Label
2817 or else Nkind (Stm) in N_Push_xxx_Label
2822 -- Do the test on the original statement before expansion
2825 Ostm : constant Node_Id := Original_Node (Stm);
2828 -- If explicit raise statement, turn on flag
2830 if Nkind (Ostm) = N_Raise_Statement then
2831 Set_Trivial_Subprogram (Stm);
2833 -- If null statement, and no following statements, turn on flag
2835 elsif Nkind (Stm) = N_Null_Statement
2836 and then Comes_From_Source (Stm)
2837 and then No (Next (Stm))
2839 Set_Trivial_Subprogram (Stm);
2841 -- Check for explicit call cases which likely raise an exception
2843 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
2844 if Is_Entity_Name (Name (Ostm)) then
2846 Ent : constant Entity_Id := Entity (Name (Ostm));
2849 -- If the procedure is marked No_Return, then likely it
2850 -- raises an exception, but in any case it is not coming
2851 -- back here, so turn on the flag.
2854 and then Ekind (Ent) = E_Procedure
2855 and then No_Return (Ent)
2857 Set_Trivial_Subprogram (Stm);
2865 -- Check for variables that are never modified
2871 -- If there is a separate spec, then transfer Never_Set_In_Source
2872 -- flags from out parameters to the corresponding entities in the
2873 -- body. The reason we do that is we want to post error flags on
2874 -- the body entities, not the spec entities.
2876 if Present (Spec_Id) then
2877 E1 := First_Entity (Spec_Id);
2878 while Present (E1) loop
2879 if Ekind (E1) = E_Out_Parameter then
2880 E2 := First_Entity (Body_Id);
2881 while Present (E2) loop
2882 exit when Chars (E1) = Chars (E2);
2886 if Present (E2) then
2887 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
2895 -- Check references in body unless it was deleted. Note that the
2896 -- check of Body_Deleted here is not just for efficiency, it is
2897 -- necessary to avoid junk warnings on formal parameters.
2899 if not Body_Deleted then
2900 Check_References (Body_Id);
2903 end Analyze_Subprogram_Body_Helper;
2905 ------------------------------------
2906 -- Analyze_Subprogram_Declaration --
2907 ------------------------------------
2909 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
2910 Loc : constant Source_Ptr := Sloc (N);
2911 Scop : constant Entity_Id := Current_Scope;
2912 Designator : Entity_Id;
2914 Null_Body : Node_Id := Empty;
2916 -- Start of processing for Analyze_Subprogram_Declaration
2919 -- Null procedures are not allowed in SPARK
2921 if Nkind (Specification (N)) = N_Procedure_Specification
2922 and then Null_Present (Specification (N))
2924 Check_SPARK_Restriction ("null procedure is not allowed", N);
2927 -- For a null procedure, capture the profile before analysis, for
2928 -- expansion at the freeze point and at each point of call. The body
2929 -- will only be used if the procedure has preconditions. In that case
2930 -- the body is analyzed at the freeze point.
2932 if Nkind (Specification (N)) = N_Procedure_Specification
2933 and then Null_Present (Specification (N))
2934 and then Expander_Active
2937 Make_Subprogram_Body (Loc,
2939 New_Copy_Tree (Specification (N)),
2942 Handled_Statement_Sequence =>
2943 Make_Handled_Sequence_Of_Statements (Loc,
2944 Statements => New_List (Make_Null_Statement (Loc))));
2946 -- Create new entities for body and formals
2948 Set_Defining_Unit_Name (Specification (Null_Body),
2949 Make_Defining_Identifier (Loc, Chars (Defining_Entity (N))));
2950 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
2952 Form := First (Parameter_Specifications (Specification (Null_Body)));
2953 while Present (Form) loop
2954 Set_Defining_Identifier (Form,
2955 Make_Defining_Identifier (Loc,
2956 Chars (Defining_Identifier (Form))));
2958 -- Resolve the types of the formals now, because the freeze point
2959 -- may appear in a different context, e.g. an instantiation.
2961 if Nkind (Parameter_Type (Form)) /= N_Access_Definition then
2962 Find_Type (Parameter_Type (Form));
2965 No (Access_To_Subprogram_Definition (Parameter_Type (Form)))
2967 Find_Type (Subtype_Mark (Parameter_Type (Form)));
2971 -- the case of a null procedure with a formal that is an
2972 -- access_to_subprogram type, and that is used as an actual
2973 -- in an instantiation is left to the enthusiastic reader.
2981 if Is_Protected_Type (Current_Scope) then
2982 Error_Msg_N ("protected operation cannot be a null procedure", N);
2986 Designator := Analyze_Subprogram_Specification (Specification (N));
2987 Generate_Definition (Designator);
2988 -- ??? why this call, already in Analyze_Subprogram_Specification
2990 if Debug_Flag_C then
2991 Write_Str ("==> subprogram spec ");
2992 Write_Name (Chars (Designator));
2993 Write_Str (" from ");
2994 Write_Location (Sloc (N));
2999 if Nkind (Specification (N)) = N_Procedure_Specification
3000 and then Null_Present (Specification (N))
3002 Set_Has_Completion (Designator);
3004 if Present (Null_Body) then
3005 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
3006 Set_Body_To_Inline (N, Null_Body);
3007 Set_Is_Inlined (Designator);
3011 Validate_RCI_Subprogram_Declaration (N);
3012 New_Overloaded_Entity (Designator);
3013 Check_Delayed_Subprogram (Designator);
3015 -- If the type of the first formal of the current subprogram is a
3016 -- nongeneric tagged private type, mark the subprogram as being a
3017 -- private primitive. Ditto if this is a function with controlling
3018 -- result, and the return type is currently private. In both cases,
3019 -- the type of the controlling argument or result must be in the
3020 -- current scope for the operation to be primitive.
3022 if Has_Controlling_Result (Designator)
3023 and then Is_Private_Type (Etype (Designator))
3024 and then Scope (Etype (Designator)) = Current_Scope
3025 and then not Is_Generic_Actual_Type (Etype (Designator))
3027 Set_Is_Private_Primitive (Designator);
3029 elsif Present (First_Formal (Designator)) then
3031 Formal_Typ : constant Entity_Id :=
3032 Etype (First_Formal (Designator));
3034 Set_Is_Private_Primitive (Designator,
3035 Is_Tagged_Type (Formal_Typ)
3036 and then Scope (Formal_Typ) = Current_Scope
3037 and then Is_Private_Type (Formal_Typ)
3038 and then not Is_Generic_Actual_Type (Formal_Typ));
3042 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
3045 if Ada_Version >= Ada_2005
3046 and then Comes_From_Source (N)
3047 and then Is_Dispatching_Operation (Designator)
3054 if Has_Controlling_Result (Designator) then
3055 Etyp := Etype (Designator);
3058 E := First_Entity (Designator);
3060 and then Is_Formal (E)
3061 and then not Is_Controlling_Formal (E)
3069 if Is_Access_Type (Etyp) then
3070 Etyp := Directly_Designated_Type (Etyp);
3073 if Is_Interface (Etyp)
3074 and then not Is_Abstract_Subprogram (Designator)
3075 and then not (Ekind (Designator) = E_Procedure
3076 and then Null_Present (Specification (N)))
3078 Error_Msg_Name_1 := Chars (Defining_Entity (N));
3080 ("(Ada 2005) interface subprogram % must be abstract or null",
3086 -- What is the following code for, it used to be
3088 -- ??? Set_Suppress_Elaboration_Checks
3089 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
3091 -- The following seems equivalent, but a bit dubious
3093 if Elaboration_Checks_Suppressed (Designator) then
3094 Set_Kill_Elaboration_Checks (Designator);
3097 if Scop /= Standard_Standard
3098 and then not Is_Child_Unit (Designator)
3100 Set_Categorization_From_Scope (Designator, Scop);
3102 -- For a compilation unit, check for library-unit pragmas
3104 Push_Scope (Designator);
3105 Set_Categorization_From_Pragmas (N);
3106 Validate_Categorization_Dependency (N, Designator);
3110 -- For a compilation unit, set body required. This flag will only be
3111 -- reset if a valid Import or Interface pragma is processed later on.
3113 if Nkind (Parent (N)) = N_Compilation_Unit then
3114 Set_Body_Required (Parent (N), True);
3116 if Ada_Version >= Ada_2005
3117 and then Nkind (Specification (N)) = N_Procedure_Specification
3118 and then Null_Present (Specification (N))
3121 ("null procedure cannot be declared at library level", N);
3125 Generate_Reference_To_Formals (Designator);
3126 Check_Eliminated (Designator);
3128 if Debug_Flag_C then
3130 Write_Str ("<== subprogram spec ");
3131 Write_Name (Chars (Designator));
3132 Write_Str (" from ");
3133 Write_Location (Sloc (N));
3137 if Is_Protected_Type (Current_Scope) then
3139 -- Indicate that this is a protected operation, because it may be
3140 -- used in subsequent declarations within the protected type.
3142 Set_Convention (Designator, Convention_Protected);
3145 List_Inherited_Pre_Post_Aspects (Designator);
3147 if Has_Aspects (N) then
3148 Analyze_Aspect_Specifications (N, Designator);
3150 end Analyze_Subprogram_Declaration;
3152 --------------------------------------
3153 -- Analyze_Subprogram_Specification --
3154 --------------------------------------
3156 -- Reminder: N here really is a subprogram specification (not a subprogram
3157 -- declaration). This procedure is called to analyze the specification in
3158 -- both subprogram bodies and subprogram declarations (specs).
3160 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
3161 Designator : constant Entity_Id := Defining_Entity (N);
3162 Formals : constant List_Id := Parameter_Specifications (N);
3164 -- Start of processing for Analyze_Subprogram_Specification
3167 -- User-defined operator is not allowed in SPARK, except as a renaming
3169 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
3170 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
3172 Check_SPARK_Restriction ("user-defined operator is not allowed", N);
3175 -- Proceed with analysis
3177 Generate_Definition (Designator);
3178 Set_Contract (Designator, Make_Contract (Sloc (Designator)));
3180 if Nkind (N) = N_Function_Specification then
3181 Set_Ekind (Designator, E_Function);
3182 Set_Mechanism (Designator, Default_Mechanism);
3184 Set_Ekind (Designator, E_Procedure);
3185 Set_Etype (Designator, Standard_Void_Type);
3188 -- Introduce new scope for analysis of the formals and the return type
3190 Set_Scope (Designator, Current_Scope);
3192 if Present (Formals) then
3193 Push_Scope (Designator);
3194 Process_Formals (Formals, N);
3196 -- Ada 2005 (AI-345): If this is an overriding operation of an
3197 -- inherited interface operation, and the controlling type is
3198 -- a synchronized type, replace the type with its corresponding
3199 -- record, to match the proper signature of an overriding operation.
3200 -- Same processing for an access parameter whose designated type is
3201 -- derived from a synchronized interface.
3203 if Ada_Version >= Ada_2005 then
3206 Formal_Typ : Entity_Id;
3207 Rec_Typ : Entity_Id;
3208 Desig_Typ : Entity_Id;
3211 Formal := First_Formal (Designator);
3212 while Present (Formal) loop
3213 Formal_Typ := Etype (Formal);
3215 if Is_Concurrent_Type (Formal_Typ)
3216 and then Present (Corresponding_Record_Type (Formal_Typ))
3218 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
3220 if Present (Interfaces (Rec_Typ)) then
3221 Set_Etype (Formal, Rec_Typ);
3224 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
3225 Desig_Typ := Designated_Type (Formal_Typ);
3227 if Is_Concurrent_Type (Desig_Typ)
3228 and then Present (Corresponding_Record_Type (Desig_Typ))
3230 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
3232 if Present (Interfaces (Rec_Typ)) then
3233 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
3238 Next_Formal (Formal);
3245 -- The subprogram scope is pushed and popped around the processing of
3246 -- the return type for consistency with call above to Process_Formals
3247 -- (which itself can call Analyze_Return_Type), and to ensure that any
3248 -- itype created for the return type will be associated with the proper
3251 elsif Nkind (N) = N_Function_Specification then
3252 Push_Scope (Designator);
3253 Analyze_Return_Type (N);
3259 if Nkind (N) = N_Function_Specification then
3261 -- Deal with operator symbol case
3263 if Nkind (Designator) = N_Defining_Operator_Symbol then
3264 Valid_Operator_Definition (Designator);
3267 May_Need_Actuals (Designator);
3269 -- Ada 2005 (AI-251): If the return type is abstract, verify that
3270 -- the subprogram is abstract also. This does not apply to renaming
3271 -- declarations, where abstractness is inherited.
3273 -- In case of primitives associated with abstract interface types
3274 -- the check is applied later (see Analyze_Subprogram_Declaration).
3276 if not Nkind_In (Parent (N), N_Subprogram_Renaming_Declaration,
3277 N_Abstract_Subprogram_Declaration,
3278 N_Formal_Abstract_Subprogram_Declaration)
3280 if Is_Abstract_Type (Etype (Designator))
3281 and then not Is_Interface (Etype (Designator))
3284 ("function that returns abstract type must be abstract", N);
3286 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
3287 -- access result whose designated type is abstract.
3289 elsif Nkind (Result_Definition (N)) = N_Access_Definition
3291 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
3292 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
3293 and then Ada_Version >= Ada_2012
3295 Error_Msg_N ("function whose access result designates "
3296 & "abstract type must be abstract", N);
3302 end Analyze_Subprogram_Specification;
3304 --------------------------
3305 -- Build_Body_To_Inline --
3306 --------------------------
3308 procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id) is
3309 Decl : constant Node_Id := Unit_Declaration_Node (Subp);
3310 Original_Body : Node_Id;
3311 Body_To_Analyze : Node_Id;
3312 Max_Size : constant := 10;
3313 Stat_Count : Integer := 0;
3315 function Has_Excluded_Declaration (Decls : List_Id) return Boolean;
3316 -- Check for declarations that make inlining not worthwhile
3318 function Has_Excluded_Statement (Stats : List_Id) return Boolean;
3319 -- Check for statements that make inlining not worthwhile: any tasking
3320 -- statement, nested at any level. Keep track of total number of
3321 -- elementary statements, as a measure of acceptable size.
3323 function Has_Pending_Instantiation return Boolean;
3324 -- If some enclosing body contains instantiations that appear before the
3325 -- corresponding generic body, the enclosing body has a freeze node so
3326 -- that it can be elaborated after the generic itself. This might
3327 -- conflict with subsequent inlinings, so that it is unsafe to try to
3328 -- inline in such a case.
3330 function Has_Single_Return return Boolean;
3331 -- In general we cannot inline functions that return unconstrained type.
3332 -- However, we can handle such functions if all return statements return
3333 -- a local variable that is the only declaration in the body of the
3334 -- function. In that case the call can be replaced by that local
3335 -- variable as is done for other inlined calls.
3337 procedure Remove_Pragmas;
3338 -- A pragma Unreferenced or pragma Unmodified that mentions a formal
3339 -- parameter has no meaning when the body is inlined and the formals
3340 -- are rewritten. Remove it from body to inline. The analysis of the
3341 -- non-inlined body will handle the pragma properly.
3343 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean;
3344 -- If the body of the subprogram includes a call that returns an
3345 -- unconstrained type, the secondary stack is involved, and it
3346 -- is not worth inlining.
3348 ------------------------------
3349 -- Has_Excluded_Declaration --
3350 ------------------------------
3352 function Has_Excluded_Declaration (Decls : List_Id) return Boolean is
3355 function Is_Unchecked_Conversion (D : Node_Id) return Boolean;
3356 -- Nested subprograms make a given body ineligible for inlining, but
3357 -- we make an exception for instantiations of unchecked conversion.
3358 -- The body has not been analyzed yet, so check the name, and verify
3359 -- that the visible entity with that name is the predefined unit.
3361 -----------------------------
3362 -- Is_Unchecked_Conversion --
3363 -----------------------------
3365 function Is_Unchecked_Conversion (D : Node_Id) return Boolean is
3366 Id : constant Node_Id := Name (D);
3370 if Nkind (Id) = N_Identifier
3371 and then Chars (Id) = Name_Unchecked_Conversion
3373 Conv := Current_Entity (Id);
3375 elsif Nkind_In (Id, N_Selected_Component, N_Expanded_Name)
3376 and then Chars (Selector_Name (Id)) = Name_Unchecked_Conversion
3378 Conv := Current_Entity (Selector_Name (Id));
3383 return Present (Conv)
3384 and then Is_Predefined_File_Name
3385 (Unit_File_Name (Get_Source_Unit (Conv)))
3386 and then Is_Intrinsic_Subprogram (Conv);
3387 end Is_Unchecked_Conversion;
3389 -- Start of processing for Has_Excluded_Declaration
3393 while Present (D) loop
3394 if (Nkind (D) = N_Function_Instantiation
3395 and then not Is_Unchecked_Conversion (D))
3396 or else Nkind_In (D, N_Protected_Type_Declaration,
3397 N_Package_Declaration,
3398 N_Package_Instantiation,
3400 N_Procedure_Instantiation,
3401 N_Task_Type_Declaration)
3404 ("cannot inline & (non-allowed declaration)?", D, Subp);
3412 end Has_Excluded_Declaration;
3414 ----------------------------
3415 -- Has_Excluded_Statement --
3416 ----------------------------
3418 function Has_Excluded_Statement (Stats : List_Id) return Boolean is
3424 while Present (S) loop
3425 Stat_Count := Stat_Count + 1;
3427 if Nkind_In (S, N_Abort_Statement,
3428 N_Asynchronous_Select,
3429 N_Conditional_Entry_Call,
3430 N_Delay_Relative_Statement,
3431 N_Delay_Until_Statement,
3436 ("cannot inline & (non-allowed statement)?", S, Subp);
3439 elsif Nkind (S) = N_Block_Statement then
3440 if Present (Declarations (S))
3441 and then Has_Excluded_Declaration (Declarations (S))
3445 elsif Present (Handled_Statement_Sequence (S))
3448 (Exception_Handlers (Handled_Statement_Sequence (S)))
3450 Has_Excluded_Statement
3451 (Statements (Handled_Statement_Sequence (S))))
3456 elsif Nkind (S) = N_Case_Statement then
3457 E := First (Alternatives (S));
3458 while Present (E) loop
3459 if Has_Excluded_Statement (Statements (E)) then
3466 elsif Nkind (S) = N_If_Statement then
3467 if Has_Excluded_Statement (Then_Statements (S)) then
3471 if Present (Elsif_Parts (S)) then
3472 E := First (Elsif_Parts (S));
3473 while Present (E) loop
3474 if Has_Excluded_Statement (Then_Statements (E)) then
3481 if Present (Else_Statements (S))
3482 and then Has_Excluded_Statement (Else_Statements (S))
3487 elsif Nkind (S) = N_Loop_Statement
3488 and then Has_Excluded_Statement (Statements (S))
3492 elsif Nkind (S) = N_Extended_Return_Statement then
3493 if Has_Excluded_Statement
3494 (Statements (Handled_Statement_Sequence (S)))
3496 (Exception_Handlers (Handled_Statement_Sequence (S)))
3506 end Has_Excluded_Statement;
3508 -------------------------------
3509 -- Has_Pending_Instantiation --
3510 -------------------------------
3512 function Has_Pending_Instantiation return Boolean is
3517 while Present (S) loop
3518 if Is_Compilation_Unit (S)
3519 or else Is_Child_Unit (S)
3523 elsif Ekind (S) = E_Package
3524 and then Has_Forward_Instantiation (S)
3533 end Has_Pending_Instantiation;
3535 ------------------------
3536 -- Has_Single_Return --
3537 ------------------------
3539 function Has_Single_Return return Boolean is
3540 Return_Statement : Node_Id := Empty;
3542 function Check_Return (N : Node_Id) return Traverse_Result;
3548 function Check_Return (N : Node_Id) return Traverse_Result is
3550 if Nkind (N) = N_Simple_Return_Statement then
3551 if Present (Expression (N))
3552 and then Is_Entity_Name (Expression (N))
3554 if No (Return_Statement) then
3555 Return_Statement := N;
3558 elsif Chars (Expression (N)) =
3559 Chars (Expression (Return_Statement))
3567 -- A return statement within an extended return is a noop
3570 elsif No (Expression (N))
3571 and then Nkind (Parent (Parent (N))) =
3572 N_Extended_Return_Statement
3577 -- Expression has wrong form
3582 -- We can only inline a build-in-place function if
3583 -- it has a single extended return.
3585 elsif Nkind (N) = N_Extended_Return_Statement then
3586 if No (Return_Statement) then
3587 Return_Statement := N;
3599 function Check_All_Returns is new Traverse_Func (Check_Return);
3601 -- Start of processing for Has_Single_Return
3604 if Check_All_Returns (N) /= OK then
3607 elsif Nkind (Return_Statement) = N_Extended_Return_Statement then
3611 return Present (Declarations (N))
3612 and then Present (First (Declarations (N)))
3613 and then Chars (Expression (Return_Statement)) =
3614 Chars (Defining_Identifier (First (Declarations (N))));
3616 end Has_Single_Return;
3618 --------------------
3619 -- Remove_Pragmas --
3620 --------------------
3622 procedure Remove_Pragmas is
3627 Decl := First (Declarations (Body_To_Analyze));
3628 while Present (Decl) loop
3631 if Nkind (Decl) = N_Pragma
3632 and then (Pragma_Name (Decl) = Name_Unreferenced
3634 Pragma_Name (Decl) = Name_Unmodified)
3643 --------------------------
3644 -- Uses_Secondary_Stack --
3645 --------------------------
3647 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean is
3648 function Check_Call (N : Node_Id) return Traverse_Result;
3649 -- Look for function calls that return an unconstrained type
3655 function Check_Call (N : Node_Id) return Traverse_Result is
3657 if Nkind (N) = N_Function_Call
3658 and then Is_Entity_Name (Name (N))
3659 and then Is_Composite_Type (Etype (Entity (Name (N))))
3660 and then not Is_Constrained (Etype (Entity (Name (N))))
3663 ("cannot inline & (call returns unconstrained type)?",
3671 function Check_Calls is new Traverse_Func (Check_Call);
3674 return Check_Calls (Bod) = Abandon;
3675 end Uses_Secondary_Stack;
3677 -- Start of processing for Build_Body_To_Inline
3680 -- Return immediately if done already
3682 if Nkind (Decl) = N_Subprogram_Declaration
3683 and then Present (Body_To_Inline (Decl))
3687 -- Functions that return unconstrained composite types require
3688 -- secondary stack handling, and cannot currently be inlined, unless
3689 -- all return statements return a local variable that is the first
3690 -- local declaration in the body.
3692 elsif Ekind (Subp) = E_Function
3693 and then not Is_Scalar_Type (Etype (Subp))
3694 and then not Is_Access_Type (Etype (Subp))
3695 and then not Is_Constrained (Etype (Subp))
3697 if not Has_Single_Return then
3699 ("cannot inline & (unconstrained return type)?", N, Subp);
3703 -- Ditto for functions that return controlled types, where controlled
3704 -- actions interfere in complex ways with inlining.
3706 elsif Ekind (Subp) = E_Function
3707 and then Needs_Finalization (Etype (Subp))
3710 ("cannot inline & (controlled return type)?", N, Subp);
3714 if Present (Declarations (N))
3715 and then Has_Excluded_Declaration (Declarations (N))
3720 if Present (Handled_Statement_Sequence (N)) then
3721 if Present (Exception_Handlers (Handled_Statement_Sequence (N))) then
3723 ("cannot inline& (exception handler)?",
3724 First (Exception_Handlers (Handled_Statement_Sequence (N))),
3728 Has_Excluded_Statement
3729 (Statements (Handled_Statement_Sequence (N)))
3735 -- We do not inline a subprogram that is too large, unless it is
3736 -- marked Inline_Always. This pragma does not suppress the other
3737 -- checks on inlining (forbidden declarations, handlers, etc).
3739 if Stat_Count > Max_Size
3740 and then not Has_Pragma_Inline_Always (Subp)
3742 Cannot_Inline ("cannot inline& (body too large)?", N, Subp);
3746 if Has_Pending_Instantiation then
3748 ("cannot inline& (forward instance within enclosing body)?",
3753 -- Within an instance, the body to inline must be treated as a nested
3754 -- generic, so that the proper global references are preserved.
3756 -- Note that we do not do this at the library level, because it is not
3757 -- needed, and furthermore this causes trouble if front end inlining
3758 -- is activated (-gnatN).
3760 if In_Instance and then Scope (Current_Scope) /= Standard_Standard then
3761 Save_Env (Scope (Current_Scope), Scope (Current_Scope));
3762 Original_Body := Copy_Generic_Node (N, Empty, True);
3764 Original_Body := Copy_Separate_Tree (N);
3767 -- We need to capture references to the formals in order to substitute
3768 -- the actuals at the point of inlining, i.e. instantiation. To treat
3769 -- the formals as globals to the body to inline, we nest it within
3770 -- a dummy parameterless subprogram, declared within the real one.
3771 -- To avoid generating an internal name (which is never public, and
3772 -- which affects serial numbers of other generated names), we use
3773 -- an internal symbol that cannot conflict with user declarations.
3775 Set_Parameter_Specifications (Specification (Original_Body), No_List);
3776 Set_Defining_Unit_Name
3777 (Specification (Original_Body),
3778 Make_Defining_Identifier (Sloc (N), Name_uParent));
3779 Set_Corresponding_Spec (Original_Body, Empty);
3781 Body_To_Analyze := Copy_Generic_Node (Original_Body, Empty, False);
3783 -- Set return type of function, which is also global and does not need
3786 if Ekind (Subp) = E_Function then
3787 Set_Result_Definition (Specification (Body_To_Analyze),
3788 New_Occurrence_Of (Etype (Subp), Sloc (N)));
3791 if No (Declarations (N)) then
3792 Set_Declarations (N, New_List (Body_To_Analyze));
3794 Append (Body_To_Analyze, Declarations (N));
3797 Expander_Mode_Save_And_Set (False);
3800 Analyze (Body_To_Analyze);
3801 Push_Scope (Defining_Entity (Body_To_Analyze));
3802 Save_Global_References (Original_Body);
3804 Remove (Body_To_Analyze);
3806 Expander_Mode_Restore;
3808 -- Restore environment if previously saved
3810 if In_Instance and then Scope (Current_Scope) /= Standard_Standard then
3814 -- If secondary stk used there is no point in inlining. We have
3815 -- already issued the warning in this case, so nothing to do.
3817 if Uses_Secondary_Stack (Body_To_Analyze) then
3821 Set_Body_To_Inline (Decl, Original_Body);
3822 Set_Ekind (Defining_Entity (Original_Body), Ekind (Subp));
3823 Set_Is_Inlined (Subp);
3824 end Build_Body_To_Inline;
3830 procedure Cannot_Inline (Msg : String; N : Node_Id; Subp : Entity_Id) is
3832 -- Do not emit warning if this is a predefined unit which is not the
3833 -- main unit. With validity checks enabled, some predefined subprograms
3834 -- may contain nested subprograms and become ineligible for inlining.
3836 if Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (Subp)))
3837 and then not In_Extended_Main_Source_Unit (Subp)
3841 elsif Has_Pragma_Inline_Always (Subp) then
3843 -- Remove last character (question mark) to make this into an error,
3844 -- because the Inline_Always pragma cannot be obeyed.
3846 Error_Msg_NE (Msg (Msg'First .. Msg'Last - 1), N, Subp);
3848 elsif Ineffective_Inline_Warnings then
3849 Error_Msg_NE (Msg, N, Subp);
3853 -----------------------
3854 -- Check_Conformance --
3855 -----------------------
3857 procedure Check_Conformance
3858 (New_Id : Entity_Id;
3860 Ctype : Conformance_Type;
3862 Conforms : out Boolean;
3863 Err_Loc : Node_Id := Empty;
3864 Get_Inst : Boolean := False;
3865 Skip_Controlling_Formals : Boolean := False)
3867 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
3868 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
3869 -- If Errmsg is True, then processing continues to post an error message
3870 -- for conformance error on given node. Two messages are output. The
3871 -- first message points to the previous declaration with a general "no
3872 -- conformance" message. The second is the detailed reason, supplied as
3873 -- Msg. The parameter N provide information for a possible & insertion
3874 -- in the message, and also provides the location for posting the
3875 -- message in the absence of a specified Err_Loc location.
3877 -----------------------
3878 -- Conformance_Error --
3879 -----------------------
3881 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
3888 if No (Err_Loc) then
3894 Error_Msg_Sloc := Sloc (Old_Id);
3897 when Type_Conformant =>
3898 Error_Msg_N -- CODEFIX
3899 ("not type conformant with declaration#!", Enode);
3901 when Mode_Conformant =>
3902 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3904 ("not mode conformant with operation inherited#!",
3908 ("not mode conformant with declaration#!", Enode);
3911 when Subtype_Conformant =>
3912 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3914 ("not subtype conformant with operation inherited#!",
3918 ("not subtype conformant with declaration#!", Enode);
3921 when Fully_Conformant =>
3922 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3923 Error_Msg_N -- CODEFIX
3924 ("not fully conformant with operation inherited#!",
3927 Error_Msg_N -- CODEFIX
3928 ("not fully conformant with declaration#!", Enode);
3932 Error_Msg_NE (Msg, Enode, N);
3934 end Conformance_Error;
3938 Old_Type : constant Entity_Id := Etype (Old_Id);
3939 New_Type : constant Entity_Id := Etype (New_Id);
3940 Old_Formal : Entity_Id;
3941 New_Formal : Entity_Id;
3942 Access_Types_Match : Boolean;
3943 Old_Formal_Base : Entity_Id;
3944 New_Formal_Base : Entity_Id;
3946 -- Start of processing for Check_Conformance
3951 -- We need a special case for operators, since they don't appear
3954 if Ctype = Type_Conformant then
3955 if Ekind (New_Id) = E_Operator
3956 and then Operator_Matches_Spec (New_Id, Old_Id)
3962 -- If both are functions/operators, check return types conform
3964 if Old_Type /= Standard_Void_Type
3965 and then New_Type /= Standard_Void_Type
3968 -- If we are checking interface conformance we omit controlling
3969 -- arguments and result, because we are only checking the conformance
3970 -- of the remaining parameters.
3972 if Has_Controlling_Result (Old_Id)
3973 and then Has_Controlling_Result (New_Id)
3974 and then Skip_Controlling_Formals
3978 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
3979 Conformance_Error ("\return type does not match!", New_Id);
3983 -- Ada 2005 (AI-231): In case of anonymous access types check the
3984 -- null-exclusion and access-to-constant attributes match.
3986 if Ada_Version >= Ada_2005
3987 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
3989 (Can_Never_Be_Null (Old_Type)
3990 /= Can_Never_Be_Null (New_Type)
3991 or else Is_Access_Constant (Etype (Old_Type))
3992 /= Is_Access_Constant (Etype (New_Type)))
3994 Conformance_Error ("\return type does not match!", New_Id);
3998 -- If either is a function/operator and the other isn't, error
4000 elsif Old_Type /= Standard_Void_Type
4001 or else New_Type /= Standard_Void_Type
4003 Conformance_Error ("\functions can only match functions!", New_Id);
4007 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
4008 -- If this is a renaming as body, refine error message to indicate that
4009 -- the conflict is with the original declaration. If the entity is not
4010 -- frozen, the conventions don't have to match, the one of the renamed
4011 -- entity is inherited.
4013 if Ctype >= Subtype_Conformant then
4014 if Convention (Old_Id) /= Convention (New_Id) then
4016 if not Is_Frozen (New_Id) then
4019 elsif Present (Err_Loc)
4020 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
4021 and then Present (Corresponding_Spec (Err_Loc))
4023 Error_Msg_Name_1 := Chars (New_Id);
4025 Name_Ada + Convention_Id'Pos (Convention (New_Id));
4026 Conformance_Error ("\prior declaration for% has convention %!");
4029 Conformance_Error ("\calling conventions do not match!");
4034 elsif Is_Formal_Subprogram (Old_Id)
4035 or else Is_Formal_Subprogram (New_Id)
4037 Conformance_Error ("\formal subprograms not allowed!");
4042 -- Deal with parameters
4044 -- Note: we use the entity information, rather than going directly
4045 -- to the specification in the tree. This is not only simpler, but
4046 -- absolutely necessary for some cases of conformance tests between
4047 -- operators, where the declaration tree simply does not exist!
4049 Old_Formal := First_Formal (Old_Id);
4050 New_Formal := First_Formal (New_Id);
4051 while Present (Old_Formal) and then Present (New_Formal) loop
4052 if Is_Controlling_Formal (Old_Formal)
4053 and then Is_Controlling_Formal (New_Formal)
4054 and then Skip_Controlling_Formals
4056 -- The controlling formals will have different types when
4057 -- comparing an interface operation with its match, but both
4058 -- or neither must be access parameters.
4060 if Is_Access_Type (Etype (Old_Formal))
4062 Is_Access_Type (Etype (New_Formal))
4064 goto Skip_Controlling_Formal;
4067 ("\access parameter does not match!", New_Formal);
4071 if Ctype = Fully_Conformant then
4073 -- Names must match. Error message is more accurate if we do
4074 -- this before checking that the types of the formals match.
4076 if Chars (Old_Formal) /= Chars (New_Formal) then
4077 Conformance_Error ("\name & does not match!", New_Formal);
4079 -- Set error posted flag on new formal as well to stop
4080 -- junk cascaded messages in some cases.
4082 Set_Error_Posted (New_Formal);
4086 -- Null exclusion must match
4088 if Null_Exclusion_Present (Parent (Old_Formal))
4090 Null_Exclusion_Present (Parent (New_Formal))
4092 -- Only give error if both come from source. This should be
4093 -- investigated some time, since it should not be needed ???
4095 if Comes_From_Source (Old_Formal)
4097 Comes_From_Source (New_Formal)
4100 ("\null exclusion for & does not match", New_Formal);
4102 -- Mark error posted on the new formal to avoid duplicated
4103 -- complaint about types not matching.
4105 Set_Error_Posted (New_Formal);
4110 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
4111 -- case occurs whenever a subprogram is being renamed and one of its
4112 -- parameters imposes a null exclusion. For example:
4114 -- type T is null record;
4115 -- type Acc_T is access T;
4116 -- subtype Acc_T_Sub is Acc_T;
4118 -- procedure P (Obj : not null Acc_T_Sub); -- itype
4119 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
4122 Old_Formal_Base := Etype (Old_Formal);
4123 New_Formal_Base := Etype (New_Formal);
4126 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
4127 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
4130 Access_Types_Match := Ada_Version >= Ada_2005
4132 -- Ensure that this rule is only applied when New_Id is a
4133 -- renaming of Old_Id.
4135 and then Nkind (Parent (Parent (New_Id))) =
4136 N_Subprogram_Renaming_Declaration
4137 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
4138 and then Present (Entity (Name (Parent (Parent (New_Id)))))
4139 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
4141 -- Now handle the allowed access-type case
4143 and then Is_Access_Type (Old_Formal_Base)
4144 and then Is_Access_Type (New_Formal_Base)
4146 -- The type kinds must match. The only exception occurs with
4147 -- multiple generics of the form:
4150 -- type F is private; type A is private;
4151 -- type F_Ptr is access F; type A_Ptr is access A;
4152 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
4153 -- package F_Pack is ... package A_Pack is
4154 -- package F_Inst is
4155 -- new F_Pack (A, A_Ptr, A_P);
4157 -- When checking for conformance between the parameters of A_P
4158 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
4159 -- because the compiler has transformed A_Ptr into a subtype of
4160 -- F_Ptr. We catch this case in the code below.
4162 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
4164 (Is_Generic_Type (Old_Formal_Base)
4165 and then Is_Generic_Type (New_Formal_Base)
4166 and then Is_Internal (New_Formal_Base)
4167 and then Etype (Etype (New_Formal_Base)) =
4169 and then Directly_Designated_Type (Old_Formal_Base) =
4170 Directly_Designated_Type (New_Formal_Base)
4171 and then ((Is_Itype (Old_Formal_Base)
4172 and then Can_Never_Be_Null (Old_Formal_Base))
4174 (Is_Itype (New_Formal_Base)
4175 and then Can_Never_Be_Null (New_Formal_Base)));
4177 -- Types must always match. In the visible part of an instance,
4178 -- usual overloading rules for dispatching operations apply, and
4179 -- we check base types (not the actual subtypes).
4181 if In_Instance_Visible_Part
4182 and then Is_Dispatching_Operation (New_Id)
4184 if not Conforming_Types
4185 (T1 => Base_Type (Etype (Old_Formal)),
4186 T2 => Base_Type (Etype (New_Formal)),
4188 Get_Inst => Get_Inst)
4189 and then not Access_Types_Match
4191 Conformance_Error ("\type of & does not match!", New_Formal);
4195 elsif not Conforming_Types
4196 (T1 => Old_Formal_Base,
4197 T2 => New_Formal_Base,
4199 Get_Inst => Get_Inst)
4200 and then not Access_Types_Match
4202 -- Don't give error message if old type is Any_Type. This test
4203 -- avoids some cascaded errors, e.g. in case of a bad spec.
4205 if Errmsg and then Old_Formal_Base = Any_Type then
4208 Conformance_Error ("\type of & does not match!", New_Formal);
4214 -- For mode conformance, mode must match
4216 if Ctype >= Mode_Conformant then
4217 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
4218 Conformance_Error ("\mode of & does not match!", New_Formal);
4221 -- Part of mode conformance for access types is having the same
4222 -- constant modifier.
4224 elsif Access_Types_Match
4225 and then Is_Access_Constant (Old_Formal_Base) /=
4226 Is_Access_Constant (New_Formal_Base)
4229 ("\constant modifier does not match!", New_Formal);
4234 if Ctype >= Subtype_Conformant then
4236 -- Ada 2005 (AI-231): In case of anonymous access types check
4237 -- the null-exclusion and access-to-constant attributes must
4238 -- match. For null exclusion, we test the types rather than the
4239 -- formals themselves, since the attribute is only set reliably
4240 -- on the formals in the Ada 95 case, and we exclude the case
4241 -- where Old_Formal is marked as controlling, to avoid errors
4242 -- when matching completing bodies with dispatching declarations
4243 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
4245 if Ada_Version >= Ada_2005
4246 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
4247 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
4249 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
4250 Can_Never_Be_Null (Etype (New_Formal))
4252 not Is_Controlling_Formal (Old_Formal))
4254 Is_Access_Constant (Etype (Old_Formal)) /=
4255 Is_Access_Constant (Etype (New_Formal)))
4257 -- Do not complain if error already posted on New_Formal. This
4258 -- avoids some redundant error messages.
4260 and then not Error_Posted (New_Formal)
4262 -- It is allowed to omit the null-exclusion in case of stream
4263 -- attribute subprograms. We recognize stream subprograms
4264 -- through their TSS-generated suffix.
4267 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
4269 if TSS_Name /= TSS_Stream_Read
4270 and then TSS_Name /= TSS_Stream_Write
4271 and then TSS_Name /= TSS_Stream_Input
4272 and then TSS_Name /= TSS_Stream_Output
4275 ("\type of & does not match!", New_Formal);
4282 -- Full conformance checks
4284 if Ctype = Fully_Conformant then
4286 -- We have checked already that names match
4288 if Parameter_Mode (Old_Formal) = E_In_Parameter then
4290 -- Check default expressions for in parameters
4293 NewD : constant Boolean :=
4294 Present (Default_Value (New_Formal));
4295 OldD : constant Boolean :=
4296 Present (Default_Value (Old_Formal));
4298 if NewD or OldD then
4300 -- The old default value has been analyzed because the
4301 -- current full declaration will have frozen everything
4302 -- before. The new default value has not been analyzed,
4303 -- so analyze it now before we check for conformance.
4306 Push_Scope (New_Id);
4307 Preanalyze_Spec_Expression
4308 (Default_Value (New_Formal), Etype (New_Formal));
4312 if not (NewD and OldD)
4313 or else not Fully_Conformant_Expressions
4314 (Default_Value (Old_Formal),
4315 Default_Value (New_Formal))
4318 ("\default expression for & does not match!",
4327 -- A couple of special checks for Ada 83 mode. These checks are
4328 -- skipped if either entity is an operator in package Standard,
4329 -- or if either old or new instance is not from the source program.
4331 if Ada_Version = Ada_83
4332 and then Sloc (Old_Id) > Standard_Location
4333 and then Sloc (New_Id) > Standard_Location
4334 and then Comes_From_Source (Old_Id)
4335 and then Comes_From_Source (New_Id)
4338 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
4339 New_Param : constant Node_Id := Declaration_Node (New_Formal);
4342 -- Explicit IN must be present or absent in both cases. This
4343 -- test is required only in the full conformance case.
4345 if In_Present (Old_Param) /= In_Present (New_Param)
4346 and then Ctype = Fully_Conformant
4349 ("\(Ada 83) IN must appear in both declarations",
4354 -- Grouping (use of comma in param lists) must be the same
4355 -- This is where we catch a misconformance like:
4358 -- A : Integer; B : Integer
4360 -- which are represented identically in the tree except
4361 -- for the setting of the flags More_Ids and Prev_Ids.
4363 if More_Ids (Old_Param) /= More_Ids (New_Param)
4364 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
4367 ("\grouping of & does not match!", New_Formal);
4373 -- This label is required when skipping controlling formals
4375 <<Skip_Controlling_Formal>>
4377 Next_Formal (Old_Formal);
4378 Next_Formal (New_Formal);
4381 if Present (Old_Formal) then
4382 Conformance_Error ("\too few parameters!");
4385 elsif Present (New_Formal) then
4386 Conformance_Error ("\too many parameters!", New_Formal);
4389 end Check_Conformance;
4391 -----------------------
4392 -- Check_Conventions --
4393 -----------------------
4395 procedure Check_Conventions (Typ : Entity_Id) is
4396 Ifaces_List : Elist_Id;
4398 procedure Check_Convention (Op : Entity_Id);
4399 -- Verify that the convention of inherited dispatching operation Op is
4400 -- consistent among all subprograms it overrides. In order to minimize
4401 -- the search, Search_From is utilized to designate a specific point in
4402 -- the list rather than iterating over the whole list once more.
4404 ----------------------
4405 -- Check_Convention --
4406 ----------------------
4408 procedure Check_Convention (Op : Entity_Id) is
4409 Iface_Elmt : Elmt_Id;
4410 Iface_Prim_Elmt : Elmt_Id;
4411 Iface_Prim : Entity_Id;
4414 Iface_Elmt := First_Elmt (Ifaces_List);
4415 while Present (Iface_Elmt) loop
4417 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
4418 while Present (Iface_Prim_Elmt) loop
4419 Iface_Prim := Node (Iface_Prim_Elmt);
4421 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
4422 and then Convention (Iface_Prim) /= Convention (Op)
4425 ("inconsistent conventions in primitive operations", Typ);
4427 Error_Msg_Name_1 := Chars (Op);
4428 Error_Msg_Name_2 := Get_Convention_Name (Convention (Op));
4429 Error_Msg_Sloc := Sloc (Op);
4431 if Comes_From_Source (Op) or else No (Alias (Op)) then
4432 if not Present (Overridden_Operation (Op)) then
4433 Error_Msg_N ("\\primitive % defined #", Typ);
4436 ("\\overriding operation % with " &
4437 "convention % defined #", Typ);
4440 else pragma Assert (Present (Alias (Op)));
4441 Error_Msg_Sloc := Sloc (Alias (Op));
4443 ("\\inherited operation % with " &
4444 "convention % defined #", Typ);
4447 Error_Msg_Name_1 := Chars (Op);
4449 Get_Convention_Name (Convention (Iface_Prim));
4450 Error_Msg_Sloc := Sloc (Iface_Prim);
4452 ("\\overridden operation % with " &
4453 "convention % defined #", Typ);
4455 -- Avoid cascading errors
4460 Next_Elmt (Iface_Prim_Elmt);
4463 Next_Elmt (Iface_Elmt);
4465 end Check_Convention;
4469 Prim_Op : Entity_Id;
4470 Prim_Op_Elmt : Elmt_Id;
4472 -- Start of processing for Check_Conventions
4475 if not Has_Interfaces (Typ) then
4479 Collect_Interfaces (Typ, Ifaces_List);
4481 -- The algorithm checks every overriding dispatching operation against
4482 -- all the corresponding overridden dispatching operations, detecting
4483 -- differences in conventions.
4485 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
4486 while Present (Prim_Op_Elmt) loop
4487 Prim_Op := Node (Prim_Op_Elmt);
4489 -- A small optimization: skip the predefined dispatching operations
4490 -- since they always have the same convention.
4492 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
4493 Check_Convention (Prim_Op);
4496 Next_Elmt (Prim_Op_Elmt);
4498 end Check_Conventions;
4500 ------------------------------
4501 -- Check_Delayed_Subprogram --
4502 ------------------------------
4504 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
4507 procedure Possible_Freeze (T : Entity_Id);
4508 -- T is the type of either a formal parameter or of the return type.
4509 -- If T is not yet frozen and needs a delayed freeze, then the
4510 -- subprogram itself must be delayed. If T is the limited view of an
4511 -- incomplete type the subprogram must be frozen as well, because
4512 -- T may depend on local types that have not been frozen yet.
4514 ---------------------
4515 -- Possible_Freeze --
4516 ---------------------
4518 procedure Possible_Freeze (T : Entity_Id) is
4520 if Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
4521 Set_Has_Delayed_Freeze (Designator);
4523 elsif Is_Access_Type (T)
4524 and then Has_Delayed_Freeze (Designated_Type (T))
4525 and then not Is_Frozen (Designated_Type (T))
4527 Set_Has_Delayed_Freeze (Designator);
4529 elsif Ekind (T) = E_Incomplete_Type and then From_With_Type (T) then
4530 Set_Has_Delayed_Freeze (Designator);
4532 -- AI05-0151: In Ada 2012, Incomplete types can appear in the profile
4533 -- of a subprogram or entry declaration.
4535 elsif Ekind (T) = E_Incomplete_Type
4536 and then Ada_Version >= Ada_2012
4538 Set_Has_Delayed_Freeze (Designator);
4541 end Possible_Freeze;
4543 -- Start of processing for Check_Delayed_Subprogram
4546 -- All subprograms, including abstract subprograms, may need a freeze
4547 -- node if some formal type or the return type needs one.
4549 Possible_Freeze (Etype (Designator));
4550 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
4552 -- Need delayed freeze if any of the formal types themselves need
4553 -- a delayed freeze and are not yet frozen.
4555 F := First_Formal (Designator);
4556 while Present (F) loop
4557 Possible_Freeze (Etype (F));
4558 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
4562 -- Mark functions that return by reference. Note that it cannot be
4563 -- done for delayed_freeze subprograms because the underlying
4564 -- returned type may not be known yet (for private types)
4566 if not Has_Delayed_Freeze (Designator)
4567 and then Expander_Active
4570 Typ : constant Entity_Id := Etype (Designator);
4571 Utyp : constant Entity_Id := Underlying_Type (Typ);
4574 if Is_Immutably_Limited_Type (Typ) then
4575 Set_Returns_By_Ref (Designator);
4577 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
4578 Set_Returns_By_Ref (Designator);
4582 end Check_Delayed_Subprogram;
4584 ------------------------------------
4585 -- Check_Discriminant_Conformance --
4586 ------------------------------------
4588 procedure Check_Discriminant_Conformance
4593 Old_Discr : Entity_Id := First_Discriminant (Prev);
4594 New_Discr : Node_Id := First (Discriminant_Specifications (N));
4595 New_Discr_Id : Entity_Id;
4596 New_Discr_Type : Entity_Id;
4598 procedure Conformance_Error (Msg : String; N : Node_Id);
4599 -- Post error message for conformance error on given node. Two messages
4600 -- are output. The first points to the previous declaration with a
4601 -- general "no conformance" message. The second is the detailed reason,
4602 -- supplied as Msg. The parameter N provide information for a possible
4603 -- & insertion in the message.
4605 -----------------------
4606 -- Conformance_Error --
4607 -----------------------
4609 procedure Conformance_Error (Msg : String; N : Node_Id) is
4611 Error_Msg_Sloc := Sloc (Prev_Loc);
4612 Error_Msg_N -- CODEFIX
4613 ("not fully conformant with declaration#!", N);
4614 Error_Msg_NE (Msg, N, N);
4615 end Conformance_Error;
4617 -- Start of processing for Check_Discriminant_Conformance
4620 while Present (Old_Discr) and then Present (New_Discr) loop
4622 New_Discr_Id := Defining_Identifier (New_Discr);
4624 -- The subtype mark of the discriminant on the full type has not
4625 -- been analyzed so we do it here. For an access discriminant a new
4628 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
4630 Access_Definition (N, Discriminant_Type (New_Discr));
4633 Analyze (Discriminant_Type (New_Discr));
4634 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
4636 -- Ada 2005: if the discriminant definition carries a null
4637 -- exclusion, create an itype to check properly for consistency
4638 -- with partial declaration.
4640 if Is_Access_Type (New_Discr_Type)
4641 and then Null_Exclusion_Present (New_Discr)
4644 Create_Null_Excluding_Itype
4645 (T => New_Discr_Type,
4646 Related_Nod => New_Discr,
4647 Scope_Id => Current_Scope);
4651 if not Conforming_Types
4652 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
4654 Conformance_Error ("type of & does not match!", New_Discr_Id);
4657 -- Treat the new discriminant as an occurrence of the old one,
4658 -- for navigation purposes, and fill in some semantic
4659 -- information, for completeness.
4661 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
4662 Set_Etype (New_Discr_Id, Etype (Old_Discr));
4663 Set_Scope (New_Discr_Id, Scope (Old_Discr));
4668 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
4669 Conformance_Error ("name & does not match!", New_Discr_Id);
4673 -- Default expressions must match
4676 NewD : constant Boolean :=
4677 Present (Expression (New_Discr));
4678 OldD : constant Boolean :=
4679 Present (Expression (Parent (Old_Discr)));
4682 if NewD or OldD then
4684 -- The old default value has been analyzed and expanded,
4685 -- because the current full declaration will have frozen
4686 -- everything before. The new default values have not been
4687 -- expanded, so expand now to check conformance.
4690 Preanalyze_Spec_Expression
4691 (Expression (New_Discr), New_Discr_Type);
4694 if not (NewD and OldD)
4695 or else not Fully_Conformant_Expressions
4696 (Expression (Parent (Old_Discr)),
4697 Expression (New_Discr))
4701 ("default expression for & does not match!",
4708 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
4710 if Ada_Version = Ada_83 then
4712 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
4715 -- Grouping (use of comma in param lists) must be the same
4716 -- This is where we catch a misconformance like:
4719 -- A : Integer; B : Integer
4721 -- which are represented identically in the tree except
4722 -- for the setting of the flags More_Ids and Prev_Ids.
4724 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
4725 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
4728 ("grouping of & does not match!", New_Discr_Id);
4734 Next_Discriminant (Old_Discr);
4738 if Present (Old_Discr) then
4739 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
4742 elsif Present (New_Discr) then
4744 ("too many discriminants!", Defining_Identifier (New_Discr));
4747 end Check_Discriminant_Conformance;
4749 ----------------------------
4750 -- Check_Fully_Conformant --
4751 ----------------------------
4753 procedure Check_Fully_Conformant
4754 (New_Id : Entity_Id;
4756 Err_Loc : Node_Id := Empty)
4759 pragma Warnings (Off, Result);
4762 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
4763 end Check_Fully_Conformant;
4765 ---------------------------
4766 -- Check_Mode_Conformant --
4767 ---------------------------
4769 procedure Check_Mode_Conformant
4770 (New_Id : Entity_Id;
4772 Err_Loc : Node_Id := Empty;
4773 Get_Inst : Boolean := False)
4776 pragma Warnings (Off, Result);
4779 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
4780 end Check_Mode_Conformant;
4782 --------------------------------
4783 -- Check_Overriding_Indicator --
4784 --------------------------------
4786 procedure Check_Overriding_Indicator
4788 Overridden_Subp : Entity_Id;
4789 Is_Primitive : Boolean)
4795 -- No overriding indicator for literals
4797 if Ekind (Subp) = E_Enumeration_Literal then
4800 elsif Ekind (Subp) = E_Entry then
4801 Decl := Parent (Subp);
4803 -- No point in analyzing a malformed operator
4805 elsif Nkind (Subp) = N_Defining_Operator_Symbol
4806 and then Error_Posted (Subp)
4811 Decl := Unit_Declaration_Node (Subp);
4814 if Nkind_In (Decl, N_Subprogram_Body,
4815 N_Subprogram_Body_Stub,
4816 N_Subprogram_Declaration,
4817 N_Abstract_Subprogram_Declaration,
4818 N_Subprogram_Renaming_Declaration)
4820 Spec := Specification (Decl);
4822 elsif Nkind (Decl) = N_Entry_Declaration then
4829 -- The overriding operation is type conformant with the overridden one,
4830 -- but the names of the formals are not required to match. If the names
4831 -- appear permuted in the overriding operation, this is a possible
4832 -- source of confusion that is worth diagnosing. Controlling formals
4833 -- often carry names that reflect the type, and it is not worthwhile
4834 -- requiring that their names match.
4836 if Present (Overridden_Subp)
4837 and then Nkind (Subp) /= N_Defining_Operator_Symbol
4844 Form1 := First_Formal (Subp);
4845 Form2 := First_Formal (Overridden_Subp);
4847 -- If the overriding operation is a synchronized operation, skip
4848 -- the first parameter of the overridden operation, which is
4849 -- implicit in the new one. If the operation is declared in the
4850 -- body it is not primitive and all formals must match.
4852 if Is_Concurrent_Type (Scope (Subp))
4853 and then Is_Tagged_Type (Scope (Subp))
4854 and then not Has_Completion (Scope (Subp))
4856 Form2 := Next_Formal (Form2);
4859 if Present (Form1) then
4860 Form1 := Next_Formal (Form1);
4861 Form2 := Next_Formal (Form2);
4864 while Present (Form1) loop
4865 if not Is_Controlling_Formal (Form1)
4866 and then Present (Next_Formal (Form2))
4867 and then Chars (Form1) = Chars (Next_Formal (Form2))
4869 Error_Msg_Node_2 := Alias (Overridden_Subp);
4870 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
4872 ("& does not match corresponding formal of&#",
4877 Next_Formal (Form1);
4878 Next_Formal (Form2);
4883 -- If there is an overridden subprogram, then check that there is no
4884 -- "not overriding" indicator, and mark the subprogram as overriding.
4885 -- This is not done if the overridden subprogram is marked as hidden,
4886 -- which can occur for the case of inherited controlled operations
4887 -- (see Derive_Subprogram), unless the inherited subprogram's parent
4888 -- subprogram is not itself hidden. (Note: This condition could probably
4889 -- be simplified, leaving out the testing for the specific controlled
4890 -- cases, but it seems safer and clearer this way, and echoes similar
4891 -- special-case tests of this kind in other places.)
4893 if Present (Overridden_Subp)
4894 and then (not Is_Hidden (Overridden_Subp)
4896 ((Chars (Overridden_Subp) = Name_Initialize
4898 Chars (Overridden_Subp) = Name_Adjust
4900 Chars (Overridden_Subp) = Name_Finalize)
4901 and then Present (Alias (Overridden_Subp))
4902 and then not Is_Hidden (Alias (Overridden_Subp))))
4904 if Must_Not_Override (Spec) then
4905 Error_Msg_Sloc := Sloc (Overridden_Subp);
4907 if Ekind (Subp) = E_Entry then
4909 ("entry & overrides inherited operation #", Spec, Subp);
4912 ("subprogram & overrides inherited operation #", Spec, Subp);
4915 elsif Is_Subprogram (Subp) then
4916 if Is_Init_Proc (Subp) then
4919 elsif No (Overridden_Operation (Subp)) then
4921 -- For entities generated by Derive_Subprograms the overridden
4922 -- operation is the inherited primitive (which is available
4923 -- through the attribute alias)
4925 if (Is_Dispatching_Operation (Subp)
4926 or else Is_Dispatching_Operation (Overridden_Subp))
4927 and then not Comes_From_Source (Overridden_Subp)
4928 and then Find_Dispatching_Type (Overridden_Subp) =
4929 Find_Dispatching_Type (Subp)
4930 and then Present (Alias (Overridden_Subp))
4931 and then Comes_From_Source (Alias (Overridden_Subp))
4933 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
4936 Set_Overridden_Operation (Subp, Overridden_Subp);
4941 -- If primitive flag is set or this is a protected operation, then
4942 -- the operation is overriding at the point of its declaration, so
4943 -- warn if necessary. Otherwise it may have been declared before the
4944 -- operation it overrides and no check is required.
4947 and then not Must_Override (Spec)
4948 and then (Is_Primitive
4949 or else Ekind (Scope (Subp)) = E_Protected_Type)
4951 Style.Missing_Overriding (Decl, Subp);
4954 -- If Subp is an operator, it may override a predefined operation, if
4955 -- it is defined in the same scope as the type to which it applies.
4956 -- In that case Overridden_Subp is empty because of our implicit
4957 -- representation for predefined operators. We have to check whether the
4958 -- signature of Subp matches that of a predefined operator. Note that
4959 -- first argument provides the name of the operator, and the second
4960 -- argument the signature that may match that of a standard operation.
4961 -- If the indicator is overriding, then the operator must match a
4962 -- predefined signature, because we know already that there is no
4963 -- explicit overridden operation.
4965 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
4966 if Must_Not_Override (Spec) then
4968 -- If this is not a primitive or a protected subprogram, then
4969 -- "not overriding" is illegal.
4972 and then Ekind (Scope (Subp)) /= E_Protected_Type
4975 ("overriding indicator only allowed "
4976 & "if subprogram is primitive", Subp);
4978 elsif Can_Override_Operator (Subp) then
4980 ("subprogram& overrides predefined operator ", Spec, Subp);
4983 elsif Must_Override (Spec) then
4984 if No (Overridden_Operation (Subp))
4985 and then not Can_Override_Operator (Subp)
4987 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
4990 elsif not Error_Posted (Subp)
4991 and then Style_Check
4992 and then Can_Override_Operator (Subp)
4994 not Is_Predefined_File_Name
4995 (Unit_File_Name (Get_Source_Unit (Subp)))
4997 -- If style checks are enabled, indicate that the indicator is
4998 -- missing. However, at the point of declaration, the type of
4999 -- which this is a primitive operation may be private, in which
5000 -- case the indicator would be premature.
5002 if Has_Private_Declaration (Etype (Subp))
5003 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
5007 Style.Missing_Overriding (Decl, Subp);
5011 elsif Must_Override (Spec) then
5012 if Ekind (Subp) = E_Entry then
5013 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
5015 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
5018 -- If the operation is marked "not overriding" and it's not primitive
5019 -- then an error is issued, unless this is an operation of a task or
5020 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
5021 -- has been specified have already been checked above.
5023 elsif Must_Not_Override (Spec)
5024 and then not Is_Primitive
5025 and then Ekind (Subp) /= E_Entry
5026 and then Ekind (Scope (Subp)) /= E_Protected_Type
5029 ("overriding indicator only allowed if subprogram is primitive",
5033 end Check_Overriding_Indicator;
5039 -- Note: this procedure needs to know far too much about how the expander
5040 -- messes with exceptions. The use of the flag Exception_Junk and the
5041 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
5042 -- works, but is not very clean. It would be better if the expansion
5043 -- routines would leave Original_Node working nicely, and we could use
5044 -- Original_Node here to ignore all the peculiar expander messing ???
5046 procedure Check_Returns
5050 Proc : Entity_Id := Empty)
5054 procedure Check_Statement_Sequence (L : List_Id);
5055 -- Internal recursive procedure to check a list of statements for proper
5056 -- termination by a return statement (or a transfer of control or a
5057 -- compound statement that is itself internally properly terminated).
5059 ------------------------------
5060 -- Check_Statement_Sequence --
5061 ------------------------------
5063 procedure Check_Statement_Sequence (L : List_Id) is
5068 Raise_Exception_Call : Boolean;
5069 -- Set True if statement sequence terminated by Raise_Exception call
5070 -- or a Reraise_Occurrence call.
5073 Raise_Exception_Call := False;
5075 -- Get last real statement
5077 Last_Stm := Last (L);
5079 -- Deal with digging out exception handler statement sequences that
5080 -- have been transformed by the local raise to goto optimization.
5081 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
5082 -- optimization has occurred, we are looking at something like:
5085 -- original stmts in block
5089 -- goto L1; | omitted if No_Exception_Propagation
5094 -- goto L3; -- skip handler when exception not raised
5096 -- <<L1>> -- target label for local exception
5110 -- and what we have to do is to dig out the estmts1 and estmts2
5111 -- sequences (which were the original sequences of statements in
5112 -- the exception handlers) and check them.
5114 if Nkind (Last_Stm) = N_Label
5115 and then Exception_Junk (Last_Stm)
5121 exit when Nkind (Stm) /= N_Block_Statement;
5122 exit when not Exception_Junk (Stm);
5125 exit when Nkind (Stm) /= N_Label;
5126 exit when not Exception_Junk (Stm);
5127 Check_Statement_Sequence
5128 (Statements (Handled_Statement_Sequence (Next (Stm))));
5133 exit when Nkind (Stm) /= N_Goto_Statement;
5134 exit when not Exception_Junk (Stm);
5138 -- Don't count pragmas
5140 while Nkind (Last_Stm) = N_Pragma
5142 -- Don't count call to SS_Release (can happen after Raise_Exception)
5145 (Nkind (Last_Stm) = N_Procedure_Call_Statement
5147 Nkind (Name (Last_Stm)) = N_Identifier
5149 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
5151 -- Don't count exception junk
5154 (Nkind_In (Last_Stm, N_Goto_Statement,
5156 N_Object_Declaration)
5157 and then Exception_Junk (Last_Stm))
5158 or else Nkind (Last_Stm) in N_Push_xxx_Label
5159 or else Nkind (Last_Stm) in N_Pop_xxx_Label
5164 -- Here we have the "real" last statement
5166 Kind := Nkind (Last_Stm);
5168 -- Transfer of control, OK. Note that in the No_Return procedure
5169 -- case, we already diagnosed any explicit return statements, so
5170 -- we can treat them as OK in this context.
5172 if Is_Transfer (Last_Stm) then
5175 -- Check cases of explicit non-indirect procedure calls
5177 elsif Kind = N_Procedure_Call_Statement
5178 and then Is_Entity_Name (Name (Last_Stm))
5180 -- Check call to Raise_Exception procedure which is treated
5181 -- specially, as is a call to Reraise_Occurrence.
5183 -- We suppress the warning in these cases since it is likely that
5184 -- the programmer really does not expect to deal with the case
5185 -- of Null_Occurrence, and thus would find a warning about a
5186 -- missing return curious, and raising Program_Error does not
5187 -- seem such a bad behavior if this does occur.
5189 -- Note that in the Ada 2005 case for Raise_Exception, the actual
5190 -- behavior will be to raise Constraint_Error (see AI-329).
5192 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
5194 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
5196 Raise_Exception_Call := True;
5198 -- For Raise_Exception call, test first argument, if it is
5199 -- an attribute reference for a 'Identity call, then we know
5200 -- that the call cannot possibly return.
5203 Arg : constant Node_Id :=
5204 Original_Node (First_Actual (Last_Stm));
5206 if Nkind (Arg) = N_Attribute_Reference
5207 and then Attribute_Name (Arg) = Name_Identity
5214 -- If statement, need to look inside if there is an else and check
5215 -- each constituent statement sequence for proper termination.
5217 elsif Kind = N_If_Statement
5218 and then Present (Else_Statements (Last_Stm))
5220 Check_Statement_Sequence (Then_Statements (Last_Stm));
5221 Check_Statement_Sequence (Else_Statements (Last_Stm));
5223 if Present (Elsif_Parts (Last_Stm)) then
5225 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
5228 while Present (Elsif_Part) loop
5229 Check_Statement_Sequence (Then_Statements (Elsif_Part));
5237 -- Case statement, check each case for proper termination
5239 elsif Kind = N_Case_Statement then
5243 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
5244 while Present (Case_Alt) loop
5245 Check_Statement_Sequence (Statements (Case_Alt));
5246 Next_Non_Pragma (Case_Alt);
5252 -- Block statement, check its handled sequence of statements
5254 elsif Kind = N_Block_Statement then
5260 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
5269 -- Loop statement. If there is an iteration scheme, we can definitely
5270 -- fall out of the loop. Similarly if there is an exit statement, we
5271 -- can fall out. In either case we need a following return.
5273 elsif Kind = N_Loop_Statement then
5274 if Present (Iteration_Scheme (Last_Stm))
5275 or else Has_Exit (Entity (Identifier (Last_Stm)))
5279 -- A loop with no exit statement or iteration scheme is either
5280 -- an infinite loop, or it has some other exit (raise/return).
5281 -- In either case, no warning is required.
5287 -- Timed entry call, check entry call and delay alternatives
5289 -- Note: in expanded code, the timed entry call has been converted
5290 -- to a set of expanded statements on which the check will work
5291 -- correctly in any case.
5293 elsif Kind = N_Timed_Entry_Call then
5295 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
5296 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
5299 -- If statement sequence of entry call alternative is missing,
5300 -- then we can definitely fall through, and we post the error
5301 -- message on the entry call alternative itself.
5303 if No (Statements (ECA)) then
5306 -- If statement sequence of delay alternative is missing, then
5307 -- we can definitely fall through, and we post the error
5308 -- message on the delay alternative itself.
5310 -- Note: if both ECA and DCA are missing the return, then we
5311 -- post only one message, should be enough to fix the bugs.
5312 -- If not we will get a message next time on the DCA when the
5315 elsif No (Statements (DCA)) then
5318 -- Else check both statement sequences
5321 Check_Statement_Sequence (Statements (ECA));
5322 Check_Statement_Sequence (Statements (DCA));
5327 -- Conditional entry call, check entry call and else part
5329 -- Note: in expanded code, the conditional entry call has been
5330 -- converted to a set of expanded statements on which the check
5331 -- will work correctly in any case.
5333 elsif Kind = N_Conditional_Entry_Call then
5335 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
5338 -- If statement sequence of entry call alternative is missing,
5339 -- then we can definitely fall through, and we post the error
5340 -- message on the entry call alternative itself.
5342 if No (Statements (ECA)) then
5345 -- Else check statement sequence and else part
5348 Check_Statement_Sequence (Statements (ECA));
5349 Check_Statement_Sequence (Else_Statements (Last_Stm));
5355 -- If we fall through, issue appropriate message
5358 if not Raise_Exception_Call then
5360 ("?RETURN statement missing following this statement!",
5363 ("\?Program_Error may be raised at run time!",
5367 -- Note: we set Err even though we have not issued a warning
5368 -- because we still have a case of a missing return. This is
5369 -- an extremely marginal case, probably will never be noticed
5370 -- but we might as well get it right.
5374 -- Otherwise we have the case of a procedure marked No_Return
5377 if not Raise_Exception_Call then
5379 ("?implied return after this statement " &
5380 "will raise Program_Error",
5383 ("\?procedure & is marked as No_Return!",
5388 RE : constant Node_Id :=
5389 Make_Raise_Program_Error (Sloc (Last_Stm),
5390 Reason => PE_Implicit_Return);
5392 Insert_After (Last_Stm, RE);
5396 end Check_Statement_Sequence;
5398 -- Start of processing for Check_Returns
5402 Check_Statement_Sequence (Statements (HSS));
5404 if Present (Exception_Handlers (HSS)) then
5405 Handler := First_Non_Pragma (Exception_Handlers (HSS));
5406 while Present (Handler) loop
5407 Check_Statement_Sequence (Statements (Handler));
5408 Next_Non_Pragma (Handler);
5413 ----------------------------
5414 -- Check_Subprogram_Order --
5415 ----------------------------
5417 procedure Check_Subprogram_Order (N : Node_Id) is
5419 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
5420 -- This is used to check if S1 > S2 in the sense required by this
5421 -- test, for example nameab < namec, but name2 < name10.
5423 -----------------------------
5424 -- Subprogram_Name_Greater --
5425 -----------------------------
5427 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
5432 -- Remove trailing numeric parts
5435 while S1 (L1) in '0' .. '9' loop
5440 while S2 (L2) in '0' .. '9' loop
5444 -- If non-numeric parts non-equal, that's decisive
5446 if S1 (S1'First .. L1) < S2 (S2'First .. L2) then
5449 elsif S1 (S1'First .. L1) > S2 (S2'First .. L2) then
5452 -- If non-numeric parts equal, compare suffixed numeric parts. Note
5453 -- that a missing suffix is treated as numeric zero in this test.
5457 while L1 < S1'Last loop
5459 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
5463 while L2 < S2'Last loop
5465 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
5470 end Subprogram_Name_Greater;
5472 -- Start of processing for Check_Subprogram_Order
5475 -- Check body in alpha order if this is option
5478 and then Style_Check_Order_Subprograms
5479 and then Nkind (N) = N_Subprogram_Body
5480 and then Comes_From_Source (N)
5481 and then In_Extended_Main_Source_Unit (N)
5485 renames Scope_Stack.Table
5486 (Scope_Stack.Last).Last_Subprogram_Name;
5488 Body_Id : constant Entity_Id :=
5489 Defining_Entity (Specification (N));
5492 Get_Decoded_Name_String (Chars (Body_Id));
5495 if Subprogram_Name_Greater
5496 (LSN.all, Name_Buffer (1 .. Name_Len))
5498 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
5504 LSN := new String'(Name_Buffer (1 .. Name_Len));
5507 end Check_Subprogram_Order;
5509 ------------------------------
5510 -- Check_Subtype_Conformant --
5511 ------------------------------
5513 procedure Check_Subtype_Conformant
5514 (New_Id : Entity_Id;
5516 Err_Loc : Node_Id := Empty;
5517 Skip_Controlling_Formals : Boolean := False)
5520 pragma Warnings (Off, Result);
5523 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
5524 Skip_Controlling_Formals => Skip_Controlling_Formals);
5525 end Check_Subtype_Conformant;
5527 ---------------------------
5528 -- Check_Type_Conformant --
5529 ---------------------------
5531 procedure Check_Type_Conformant
5532 (New_Id : Entity_Id;
5534 Err_Loc : Node_Id := Empty)
5537 pragma Warnings (Off, Result);
5540 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
5541 end Check_Type_Conformant;
5543 ---------------------------
5544 -- Can_Override_Operator --
5545 ---------------------------
5547 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
5550 if Nkind (Subp) /= N_Defining_Operator_Symbol then
5554 Typ := Base_Type (Etype (First_Formal (Subp)));
5556 return Operator_Matches_Spec (Subp, Subp)
5557 and then Scope (Subp) = Scope (Typ)
5558 and then not Is_Class_Wide_Type (Typ);
5560 end Can_Override_Operator;
5562 ----------------------
5563 -- Conforming_Types --
5564 ----------------------
5566 function Conforming_Types
5569 Ctype : Conformance_Type;
5570 Get_Inst : Boolean := False) return Boolean
5572 Type_1 : Entity_Id := T1;
5573 Type_2 : Entity_Id := T2;
5574 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
5576 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean;
5577 -- If neither T1 nor T2 are generic actual types, or if they are in
5578 -- different scopes (e.g. parent and child instances), then verify that
5579 -- the base types are equal. Otherwise T1 and T2 must be on the same
5580 -- subtype chain. The whole purpose of this procedure is to prevent
5581 -- spurious ambiguities in an instantiation that may arise if two
5582 -- distinct generic types are instantiated with the same actual.
5584 function Find_Designated_Type (T : Entity_Id) return Entity_Id;
5585 -- An access parameter can designate an incomplete type. If the
5586 -- incomplete type is the limited view of a type from a limited_
5587 -- with_clause, check whether the non-limited view is available. If
5588 -- it is a (non-limited) incomplete type, get the full view.
5590 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean;
5591 -- Returns True if and only if either T1 denotes a limited view of T2
5592 -- or T2 denotes a limited view of T1. This can arise when the limited
5593 -- with view of a type is used in a subprogram declaration and the
5594 -- subprogram body is in the scope of a regular with clause for the
5595 -- same unit. In such a case, the two type entities can be considered
5596 -- identical for purposes of conformance checking.
5598 ----------------------
5599 -- Base_Types_Match --
5600 ----------------------
5602 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean is
5607 elsif Base_Type (T1) = Base_Type (T2) then
5609 -- The following is too permissive. A more precise test should
5610 -- check that the generic actual is an ancestor subtype of the
5613 return not Is_Generic_Actual_Type (T1)
5614 or else not Is_Generic_Actual_Type (T2)
5615 or else Scope (T1) /= Scope (T2);
5620 end Base_Types_Match;
5622 --------------------------
5623 -- Find_Designated_Type --
5624 --------------------------
5626 function Find_Designated_Type (T : Entity_Id) return Entity_Id is
5630 Desig := Directly_Designated_Type (T);
5632 if Ekind (Desig) = E_Incomplete_Type then
5634 -- If regular incomplete type, get full view if available
5636 if Present (Full_View (Desig)) then
5637 Desig := Full_View (Desig);
5639 -- If limited view of a type, get non-limited view if available,
5640 -- and check again for a regular incomplete type.
5642 elsif Present (Non_Limited_View (Desig)) then
5643 Desig := Get_Full_View (Non_Limited_View (Desig));
5648 end Find_Designated_Type;
5650 -------------------------------
5651 -- Matches_Limited_With_View --
5652 -------------------------------
5654 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean is
5656 -- In some cases a type imported through a limited_with clause, and
5657 -- its nonlimited view are both visible, for example in an anonymous
5658 -- access-to-class-wide type in a formal. Both entities designate the
5661 if From_With_Type (T1)
5662 and then T2 = Available_View (T1)
5666 elsif From_With_Type (T2)
5667 and then T1 = Available_View (T2)
5674 end Matches_Limited_With_View;
5676 -- Start of processing for Conforming_Types
5679 -- The context is an instance association for a formal
5680 -- access-to-subprogram type; the formal parameter types require
5681 -- mapping because they may denote other formal parameters of the
5685 Type_1 := Get_Instance_Of (T1);
5686 Type_2 := Get_Instance_Of (T2);
5689 -- If one of the types is a view of the other introduced by a limited
5690 -- with clause, treat these as conforming for all purposes.
5692 if Matches_Limited_With_View (T1, T2) then
5695 elsif Base_Types_Match (Type_1, Type_2) then
5696 return Ctype <= Mode_Conformant
5697 or else Subtypes_Statically_Match (Type_1, Type_2);
5699 elsif Is_Incomplete_Or_Private_Type (Type_1)
5700 and then Present (Full_View (Type_1))
5701 and then Base_Types_Match (Full_View (Type_1), Type_2)
5703 return Ctype <= Mode_Conformant
5704 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
5706 elsif Ekind (Type_2) = E_Incomplete_Type
5707 and then Present (Full_View (Type_2))
5708 and then Base_Types_Match (Type_1, Full_View (Type_2))
5710 return Ctype <= Mode_Conformant
5711 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
5713 elsif Is_Private_Type (Type_2)
5714 and then In_Instance
5715 and then Present (Full_View (Type_2))
5716 and then Base_Types_Match (Type_1, Full_View (Type_2))
5718 return Ctype <= Mode_Conformant
5719 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
5722 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
5723 -- treated recursively because they carry a signature.
5725 Are_Anonymous_Access_To_Subprogram_Types :=
5726 Ekind (Type_1) = Ekind (Type_2)
5728 (Ekind (Type_1) = E_Anonymous_Access_Subprogram_Type
5730 Ekind (Type_1) = E_Anonymous_Access_Protected_Subprogram_Type);
5732 -- Test anonymous access type case. For this case, static subtype
5733 -- matching is required for mode conformance (RM 6.3.1(15)). We check
5734 -- the base types because we may have built internal subtype entities
5735 -- to handle null-excluding types (see Process_Formals).
5737 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
5739 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
5740 or else Are_Anonymous_Access_To_Subprogram_Types -- Ada 2005 (AI-254)
5743 Desig_1 : Entity_Id;
5744 Desig_2 : Entity_Id;
5747 -- In Ada2005, access constant indicators must match for
5748 -- subtype conformance.
5750 if Ada_Version >= Ada_2005
5751 and then Ctype >= Subtype_Conformant
5753 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
5758 Desig_1 := Find_Designated_Type (Type_1);
5759 Desig_2 := Find_Designated_Type (Type_2);
5761 -- If the context is an instance association for a formal
5762 -- access-to-subprogram type; formal access parameter designated
5763 -- types require mapping because they may denote other formal
5764 -- parameters of the generic unit.
5767 Desig_1 := Get_Instance_Of (Desig_1);
5768 Desig_2 := Get_Instance_Of (Desig_2);
5771 -- It is possible for a Class_Wide_Type to be introduced for an
5772 -- incomplete type, in which case there is a separate class_ wide
5773 -- type for the full view. The types conform if their Etypes
5774 -- conform, i.e. one may be the full view of the other. This can
5775 -- only happen in the context of an access parameter, other uses
5776 -- of an incomplete Class_Wide_Type are illegal.
5778 if Is_Class_Wide_Type (Desig_1)
5780 Is_Class_Wide_Type (Desig_2)
5784 (Etype (Base_Type (Desig_1)),
5785 Etype (Base_Type (Desig_2)), Ctype);
5787 elsif Are_Anonymous_Access_To_Subprogram_Types then
5788 if Ada_Version < Ada_2005 then
5789 return Ctype = Type_Conformant
5791 Subtypes_Statically_Match (Desig_1, Desig_2);
5793 -- We must check the conformance of the signatures themselves
5797 Conformant : Boolean;
5800 (Desig_1, Desig_2, Ctype, False, Conformant);
5806 return Base_Type (Desig_1) = Base_Type (Desig_2)
5807 and then (Ctype = Type_Conformant
5809 Subtypes_Statically_Match (Desig_1, Desig_2));
5813 -- Otherwise definitely no match
5816 if ((Ekind (Type_1) = E_Anonymous_Access_Type
5817 and then Is_Access_Type (Type_2))
5818 or else (Ekind (Type_2) = E_Anonymous_Access_Type
5819 and then Is_Access_Type (Type_1)))
5822 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
5824 May_Hide_Profile := True;
5829 end Conforming_Types;
5831 --------------------------
5832 -- Create_Extra_Formals --
5833 --------------------------
5835 procedure Create_Extra_Formals (E : Entity_Id) is
5837 First_Extra : Entity_Id := Empty;
5838 Last_Extra : Entity_Id;
5839 Formal_Type : Entity_Id;
5840 P_Formal : Entity_Id := Empty;
5842 function Add_Extra_Formal
5843 (Assoc_Entity : Entity_Id;
5846 Suffix : String) return Entity_Id;
5847 -- Add an extra formal to the current list of formals and extra formals.
5848 -- The extra formal is added to the end of the list of extra formals,
5849 -- and also returned as the result. These formals are always of mode IN.
5850 -- The new formal has the type Typ, is declared in Scope, and its name
5851 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
5852 -- The following suffixes are currently used. They should not be changed
5853 -- without coordinating with CodePeer, which makes use of these to
5854 -- provide better messages.
5856 -- O denotes the Constrained bit.
5857 -- L denotes the accessibility level.
5858 -- BIP_xxx denotes an extra formal for a build-in-place function. See
5859 -- the full list in exp_ch6.BIP_Formal_Kind.
5861 ----------------------
5862 -- Add_Extra_Formal --
5863 ----------------------
5865 function Add_Extra_Formal
5866 (Assoc_Entity : Entity_Id;
5869 Suffix : String) return Entity_Id
5871 EF : constant Entity_Id :=
5872 Make_Defining_Identifier (Sloc (Assoc_Entity),
5873 Chars => New_External_Name (Chars (Assoc_Entity),
5877 -- A little optimization. Never generate an extra formal for the
5878 -- _init operand of an initialization procedure, since it could
5881 if Chars (Formal) = Name_uInit then
5885 Set_Ekind (EF, E_In_Parameter);
5886 Set_Actual_Subtype (EF, Typ);
5887 Set_Etype (EF, Typ);
5888 Set_Scope (EF, Scope);
5889 Set_Mechanism (EF, Default_Mechanism);
5890 Set_Formal_Validity (EF);
5892 if No (First_Extra) then
5894 Set_Extra_Formals (Scope, First_Extra);
5897 if Present (Last_Extra) then
5898 Set_Extra_Formal (Last_Extra, EF);
5904 end Add_Extra_Formal;
5906 -- Start of processing for Create_Extra_Formals
5909 -- We never generate extra formals if expansion is not active
5910 -- because we don't need them unless we are generating code.
5912 if not Expander_Active then
5916 -- If this is a derived subprogram then the subtypes of the parent
5917 -- subprogram's formal parameters will be used to determine the need
5918 -- for extra formals.
5920 if Is_Overloadable (E) and then Present (Alias (E)) then
5921 P_Formal := First_Formal (Alias (E));
5924 Last_Extra := Empty;
5925 Formal := First_Formal (E);
5926 while Present (Formal) loop
5927 Last_Extra := Formal;
5928 Next_Formal (Formal);
5931 -- If Extra_formals were already created, don't do it again. This
5932 -- situation may arise for subprogram types created as part of
5933 -- dispatching calls (see Expand_Dispatching_Call)
5935 if Present (Last_Extra) and then
5936 Present (Extra_Formal (Last_Extra))
5941 -- If the subprogram is a predefined dispatching subprogram then don't
5942 -- generate any extra constrained or accessibility level formals. In
5943 -- general we suppress these for internal subprograms (by not calling
5944 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
5945 -- generated stream attributes do get passed through because extra
5946 -- build-in-place formals are needed in some cases (limited 'Input).
5948 if Is_Predefined_Internal_Operation (E) then
5949 goto Test_For_BIP_Extras;
5952 Formal := First_Formal (E);
5953 while Present (Formal) loop
5955 -- Create extra formal for supporting the attribute 'Constrained.
5956 -- The case of a private type view without discriminants also
5957 -- requires the extra formal if the underlying type has defaulted
5960 if Ekind (Formal) /= E_In_Parameter then
5961 if Present (P_Formal) then
5962 Formal_Type := Etype (P_Formal);
5964 Formal_Type := Etype (Formal);
5967 -- Do not produce extra formals for Unchecked_Union parameters.
5968 -- Jump directly to the end of the loop.
5970 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
5971 goto Skip_Extra_Formal_Generation;
5974 if not Has_Discriminants (Formal_Type)
5975 and then Ekind (Formal_Type) in Private_Kind
5976 and then Present (Underlying_Type (Formal_Type))
5978 Formal_Type := Underlying_Type (Formal_Type);
5981 -- Suppress the extra formal if formal's subtype is constrained or
5982 -- indefinite, or we're compiling for Ada 2012 and the underlying
5983 -- type is tagged and limited. In Ada 2012, a limited tagged type
5984 -- can have defaulted discriminants, but 'Constrained is required
5985 -- to return True, so the formal is never needed (see AI05-0214).
5986 -- Note that this ensures consistency of calling sequences for
5987 -- dispatching operations when some types in a class have defaults
5988 -- on discriminants and others do not (and requiring the extra
5989 -- formal would introduce distributed overhead).
5991 if Has_Discriminants (Formal_Type)
5992 and then not Is_Constrained (Formal_Type)
5993 and then not Is_Indefinite_Subtype (Formal_Type)
5994 and then (Ada_Version < Ada_2012
5996 not (Is_Tagged_Type (Underlying_Type (Formal_Type))
5997 and then Is_Limited_Type (Formal_Type)))
5999 Set_Extra_Constrained
6000 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
6004 -- Create extra formal for supporting accessibility checking. This
6005 -- is done for both anonymous access formals and formals of named
6006 -- access types that are marked as controlling formals. The latter
6007 -- case can occur when Expand_Dispatching_Call creates a subprogram
6008 -- type and substitutes the types of access-to-class-wide actuals
6009 -- for the anonymous access-to-specific-type of controlling formals.
6010 -- Base_Type is applied because in cases where there is a null
6011 -- exclusion the formal may have an access subtype.
6013 -- This is suppressed if we specifically suppress accessibility
6014 -- checks at the package level for either the subprogram, or the
6015 -- package in which it resides. However, we do not suppress it
6016 -- simply if the scope has accessibility checks suppressed, since
6017 -- this could cause trouble when clients are compiled with a
6018 -- different suppression setting. The explicit checks at the
6019 -- package level are safe from this point of view.
6021 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
6022 or else (Is_Controlling_Formal (Formal)
6023 and then Is_Access_Type (Base_Type (Etype (Formal)))))
6025 (Explicit_Suppress (E, Accessibility_Check)
6027 Explicit_Suppress (Scope (E), Accessibility_Check))
6030 or else Present (Extra_Accessibility (P_Formal)))
6032 Set_Extra_Accessibility
6033 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
6036 -- This label is required when skipping extra formal generation for
6037 -- Unchecked_Union parameters.
6039 <<Skip_Extra_Formal_Generation>>
6041 if Present (P_Formal) then
6042 Next_Formal (P_Formal);
6045 Next_Formal (Formal);
6048 <<Test_For_BIP_Extras>>
6050 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
6051 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
6053 if Ada_Version >= Ada_2005 and then Is_Build_In_Place_Function (E) then
6055 Result_Subt : constant Entity_Id := Etype (E);
6057 Discard : Entity_Id;
6058 pragma Warnings (Off, Discard);
6061 -- In the case of functions with unconstrained result subtypes,
6062 -- add a 4-state formal indicating whether the return object is
6063 -- allocated by the caller (1), or should be allocated by the
6064 -- callee on the secondary stack (2), in the global heap (3), or
6065 -- in a user-defined storage pool (4). For the moment we just use
6066 -- Natural for the type of this formal. Note that this formal
6067 -- isn't usually needed in the case where the result subtype is
6068 -- constrained, but it is needed when the function has a tagged
6069 -- result, because generally such functions can be called in a
6070 -- dispatching context and such calls must be handled like calls
6071 -- to a class-wide function.
6073 if not Is_Constrained (Underlying_Type (Result_Subt))
6074 or else Is_Tagged_Type (Underlying_Type (Result_Subt))
6078 (E, Standard_Natural,
6079 E, BIP_Formal_Suffix (BIP_Alloc_Form));
6082 -- In the case of functions whose result type needs finalization,
6083 -- add an extra formal which represents the finalization master.
6085 if Needs_BIP_Finalization_Master (E) then
6088 (E, RTE (RE_Finalization_Master_Ptr),
6089 E, BIP_Formal_Suffix (BIP_Finalization_Master));
6092 -- If the result type contains tasks, we have two extra formals:
6093 -- the master of the tasks to be created, and the caller's
6094 -- activation chain.
6096 if Has_Task (Result_Subt) then
6099 (E, RTE (RE_Master_Id),
6100 E, BIP_Formal_Suffix (BIP_Master));
6103 (E, RTE (RE_Activation_Chain_Access),
6104 E, BIP_Formal_Suffix (BIP_Activation_Chain));
6107 -- All build-in-place functions get an extra formal that will be
6108 -- passed the address of the return object within the caller.
6111 Formal_Type : constant Entity_Id :=
6113 (E_Anonymous_Access_Type, E,
6114 Scope_Id => Scope (E));
6116 Set_Directly_Designated_Type (Formal_Type, Result_Subt);
6117 Set_Etype (Formal_Type, Formal_Type);
6118 Set_Depends_On_Private
6119 (Formal_Type, Has_Private_Component (Formal_Type));
6120 Set_Is_Public (Formal_Type, Is_Public (Scope (Formal_Type)));
6121 Set_Is_Access_Constant (Formal_Type, False);
6123 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
6124 -- the designated type comes from the limited view (for
6125 -- back-end purposes).
6127 Set_From_With_Type (Formal_Type, From_With_Type (Result_Subt));
6129 Layout_Type (Formal_Type);
6133 (E, Formal_Type, E, BIP_Formal_Suffix (BIP_Object_Access));
6137 end Create_Extra_Formals;
6139 -----------------------------
6140 -- Enter_Overloaded_Entity --
6141 -----------------------------
6143 procedure Enter_Overloaded_Entity (S : Entity_Id) is
6144 E : Entity_Id := Current_Entity_In_Scope (S);
6145 C_E : Entity_Id := Current_Entity (S);
6149 Set_Has_Homonym (E);
6150 Set_Has_Homonym (S);
6153 Set_Is_Immediately_Visible (S);
6154 Set_Scope (S, Current_Scope);
6156 -- Chain new entity if front of homonym in current scope, so that
6157 -- homonyms are contiguous.
6162 while Homonym (C_E) /= E loop
6163 C_E := Homonym (C_E);
6166 Set_Homonym (C_E, S);
6170 Set_Current_Entity (S);
6175 Append_Entity (S, Current_Scope);
6176 Set_Public_Status (S);
6178 if Debug_Flag_E then
6179 Write_Str ("New overloaded entity chain: ");
6180 Write_Name (Chars (S));
6183 while Present (E) loop
6184 Write_Str (" "); Write_Int (Int (E));
6191 -- Generate warning for hiding
6194 and then Comes_From_Source (S)
6195 and then In_Extended_Main_Source_Unit (S)
6202 -- Warn unless genuine overloading. Do not emit warning on
6203 -- hiding predefined operators in Standard (these are either an
6204 -- (artifact of our implicit declarations, or simple noise) but
6205 -- keep warning on a operator defined on a local subtype, because
6206 -- of the real danger that different operators may be applied in
6207 -- various parts of the program.
6209 -- Note that if E and S have the same scope, there is never any
6210 -- hiding. Either the two conflict, and the program is illegal,
6211 -- or S is overriding an implicit inherited subprogram.
6213 if Scope (E) /= Scope (S)
6214 and then (not Is_Overloadable (E)
6215 or else Subtype_Conformant (E, S))
6216 and then (Is_Immediately_Visible (E)
6218 Is_Potentially_Use_Visible (S))
6220 if Scope (E) /= Standard_Standard then
6221 Error_Msg_Sloc := Sloc (E);
6222 Error_Msg_N ("declaration of & hides one#?", S);
6224 elsif Nkind (S) = N_Defining_Operator_Symbol
6226 Scope (Base_Type (Etype (First_Formal (S)))) /= Scope (S)
6229 ("declaration of & hides predefined operator?", S);
6234 end Enter_Overloaded_Entity;
6236 -----------------------------
6237 -- Check_Untagged_Equality --
6238 -----------------------------
6240 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
6241 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
6242 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
6246 if Nkind (Decl) = N_Subprogram_Declaration
6247 and then Is_Record_Type (Typ)
6248 and then not Is_Tagged_Type (Typ)
6250 -- If the type is not declared in a package, or if we are in the
6251 -- body of the package or in some other scope, the new operation is
6252 -- not primitive, and therefore legal, though suspicious. If the
6253 -- type is a generic actual (sub)type, the operation is not primitive
6254 -- either because the base type is declared elsewhere.
6256 if Is_Frozen (Typ) then
6257 if Ekind (Scope (Typ)) /= E_Package
6258 or else Scope (Typ) /= Current_Scope
6262 elsif Is_Generic_Actual_Type (Typ) then
6265 elsif In_Package_Body (Scope (Typ)) then
6267 ("equality operator must be declared "
6268 & "before type& is frozen", Eq_Op, Typ);
6270 ("\move declaration to package spec", Eq_Op);
6274 ("equality operator must be declared "
6275 & "before type& is frozen", Eq_Op, Typ);
6277 Obj_Decl := Next (Parent (Typ));
6278 while Present (Obj_Decl)
6279 and then Obj_Decl /= Decl
6281 if Nkind (Obj_Decl) = N_Object_Declaration
6282 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
6284 Error_Msg_NE ("type& is frozen by declaration?",
6287 ("\an equality operator cannot be declared after this "
6288 & "point (RM 4.5.2 (9.8)) (Ada 2012))?", Obj_Decl);
6296 elsif not In_Same_List (Parent (Typ), Decl)
6297 and then not Is_Limited_Type (Typ)
6300 -- This makes it illegal to have a primitive equality declared in
6301 -- the private part if the type is visible.
6303 Error_Msg_N ("equality operator appears too late", Eq_Op);
6306 end Check_Untagged_Equality;
6308 -----------------------------
6309 -- Find_Corresponding_Spec --
6310 -----------------------------
6312 function Find_Corresponding_Spec
6314 Post_Error : Boolean := True) return Entity_Id
6316 Spec : constant Node_Id := Specification (N);
6317 Designator : constant Entity_Id := Defining_Entity (Spec);
6322 E := Current_Entity (Designator);
6323 while Present (E) loop
6325 -- We are looking for a matching spec. It must have the same scope,
6326 -- and the same name, and either be type conformant, or be the case
6327 -- of a library procedure spec and its body (which belong to one
6328 -- another regardless of whether they are type conformant or not).
6330 if Scope (E) = Current_Scope then
6331 if Current_Scope = Standard_Standard
6332 or else (Ekind (E) = Ekind (Designator)
6333 and then Type_Conformant (E, Designator))
6335 -- Within an instantiation, we know that spec and body are
6336 -- subtype conformant, because they were subtype conformant
6337 -- in the generic. We choose the subtype-conformant entity
6338 -- here as well, to resolve spurious ambiguities in the
6339 -- instance that were not present in the generic (i.e. when
6340 -- two different types are given the same actual). If we are
6341 -- looking for a spec to match a body, full conformance is
6345 Set_Convention (Designator, Convention (E));
6347 -- Skip past subprogram bodies and subprogram renamings that
6348 -- may appear to have a matching spec, but that aren't fully
6349 -- conformant with it. That can occur in cases where an
6350 -- actual type causes unrelated homographs in the instance.
6352 if Nkind_In (N, N_Subprogram_Body,
6353 N_Subprogram_Renaming_Declaration)
6354 and then Present (Homonym (E))
6355 and then not Fully_Conformant (Designator, E)
6359 elsif not Subtype_Conformant (Designator, E) then
6364 if not Has_Completion (E) then
6365 if Nkind (N) /= N_Subprogram_Body_Stub then
6366 Set_Corresponding_Spec (N, E);
6369 Set_Has_Completion (E);
6372 elsif Nkind (Parent (N)) = N_Subunit then
6374 -- If this is the proper body of a subunit, the completion
6375 -- flag is set when analyzing the stub.
6379 -- If E is an internal function with a controlling result
6380 -- that was created for an operation inherited by a null
6381 -- extension, it may be overridden by a body without a previous
6382 -- spec (one more reason why these should be shunned). In that
6383 -- case remove the generated body if present, because the
6384 -- current one is the explicit overriding.
6386 elsif Ekind (E) = E_Function
6387 and then Ada_Version >= Ada_2005
6388 and then not Comes_From_Source (E)
6389 and then Has_Controlling_Result (E)
6390 and then Is_Null_Extension (Etype (E))
6391 and then Comes_From_Source (Spec)
6393 Set_Has_Completion (E, False);
6396 and then Nkind (Parent (E)) = N_Function_Specification
6399 (Unit_Declaration_Node
6400 (Corresponding_Body (Unit_Declaration_Node (E))));
6404 -- If expansion is disabled, or if the wrapper function has
6405 -- not been generated yet, this a late body overriding an
6406 -- inherited operation, or it is an overriding by some other
6407 -- declaration before the controlling result is frozen. In
6408 -- either case this is a declaration of a new entity.
6414 -- If the body already exists, then this is an error unless
6415 -- the previous declaration is the implicit declaration of a
6416 -- derived subprogram. It is also legal for an instance to
6417 -- contain type conformant overloadable declarations (but the
6418 -- generic declaration may not), per 8.3(26/2).
6420 elsif No (Alias (E))
6421 and then not Is_Intrinsic_Subprogram (E)
6422 and then not In_Instance
6425 Error_Msg_Sloc := Sloc (E);
6427 if Is_Imported (E) then
6429 ("body not allowed for imported subprogram & declared#",
6432 Error_Msg_NE ("duplicate body for & declared#", N, E);
6436 -- Child units cannot be overloaded, so a conformance mismatch
6437 -- between body and a previous spec is an error.
6439 elsif Is_Child_Unit (E)
6441 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
6443 Nkind (Parent (Unit_Declaration_Node (Designator))) =
6448 ("body of child unit does not match previous declaration", N);
6456 -- On exit, we know that no previous declaration of subprogram exists
6459 end Find_Corresponding_Spec;
6461 ----------------------
6462 -- Fully_Conformant --
6463 ----------------------
6465 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
6468 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
6470 end Fully_Conformant;
6472 ----------------------------------
6473 -- Fully_Conformant_Expressions --
6474 ----------------------------------
6476 function Fully_Conformant_Expressions
6477 (Given_E1 : Node_Id;
6478 Given_E2 : Node_Id) return Boolean
6480 E1 : constant Node_Id := Original_Node (Given_E1);
6481 E2 : constant Node_Id := Original_Node (Given_E2);
6482 -- We always test conformance on original nodes, since it is possible
6483 -- for analysis and/or expansion to make things look as though they
6484 -- conform when they do not, e.g. by converting 1+2 into 3.
6486 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
6487 renames Fully_Conformant_Expressions;
6489 function FCL (L1, L2 : List_Id) return Boolean;
6490 -- Compare elements of two lists for conformance. Elements have to
6491 -- be conformant, and actuals inserted as default parameters do not
6492 -- match explicit actuals with the same value.
6494 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
6495 -- Compare an operator node with a function call
6501 function FCL (L1, L2 : List_Id) return Boolean is
6505 if L1 = No_List then
6511 if L2 = No_List then
6517 -- Compare two lists, skipping rewrite insertions (we want to
6518 -- compare the original trees, not the expanded versions!)
6521 if Is_Rewrite_Insertion (N1) then
6523 elsif Is_Rewrite_Insertion (N2) then
6529 elsif not FCE (N1, N2) then
6542 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
6543 Actuals : constant List_Id := Parameter_Associations (Call_Node);
6548 or else Entity (Op_Node) /= Entity (Name (Call_Node))
6553 Act := First (Actuals);
6555 if Nkind (Op_Node) in N_Binary_Op then
6556 if not FCE (Left_Opnd (Op_Node), Act) then
6563 return Present (Act)
6564 and then FCE (Right_Opnd (Op_Node), Act)
6565 and then No (Next (Act));
6569 -- Start of processing for Fully_Conformant_Expressions
6572 -- Non-conformant if paren count does not match. Note: if some idiot
6573 -- complains that we don't do this right for more than 3 levels of
6574 -- parentheses, they will be treated with the respect they deserve!
6576 if Paren_Count (E1) /= Paren_Count (E2) then
6579 -- If same entities are referenced, then they are conformant even if
6580 -- they have different forms (RM 8.3.1(19-20)).
6582 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
6583 if Present (Entity (E1)) then
6584 return Entity (E1) = Entity (E2)
6585 or else (Chars (Entity (E1)) = Chars (Entity (E2))
6586 and then Ekind (Entity (E1)) = E_Discriminant
6587 and then Ekind (Entity (E2)) = E_In_Parameter);
6589 elsif Nkind (E1) = N_Expanded_Name
6590 and then Nkind (E2) = N_Expanded_Name
6591 and then Nkind (Selector_Name (E1)) = N_Character_Literal
6592 and then Nkind (Selector_Name (E2)) = N_Character_Literal
6594 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
6597 -- Identifiers in component associations don't always have
6598 -- entities, but their names must conform.
6600 return Nkind (E1) = N_Identifier
6601 and then Nkind (E2) = N_Identifier
6602 and then Chars (E1) = Chars (E2);
6605 elsif Nkind (E1) = N_Character_Literal
6606 and then Nkind (E2) = N_Expanded_Name
6608 return Nkind (Selector_Name (E2)) = N_Character_Literal
6609 and then Chars (E1) = Chars (Selector_Name (E2));
6611 elsif Nkind (E2) = N_Character_Literal
6612 and then Nkind (E1) = N_Expanded_Name
6614 return Nkind (Selector_Name (E1)) = N_Character_Literal
6615 and then Chars (E2) = Chars (Selector_Name (E1));
6617 elsif Nkind (E1) in N_Op
6618 and then Nkind (E2) = N_Function_Call
6620 return FCO (E1, E2);
6622 elsif Nkind (E2) in N_Op
6623 and then Nkind (E1) = N_Function_Call
6625 return FCO (E2, E1);
6627 -- Otherwise we must have the same syntactic entity
6629 elsif Nkind (E1) /= Nkind (E2) then
6632 -- At this point, we specialize by node type
6639 FCL (Expressions (E1), Expressions (E2))
6641 FCL (Component_Associations (E1),
6642 Component_Associations (E2));
6645 if Nkind (Expression (E1)) = N_Qualified_Expression
6647 Nkind (Expression (E2)) = N_Qualified_Expression
6649 return FCE (Expression (E1), Expression (E2));
6651 -- Check that the subtype marks and any constraints
6656 Indic1 : constant Node_Id := Expression (E1);
6657 Indic2 : constant Node_Id := Expression (E2);
6662 if Nkind (Indic1) /= N_Subtype_Indication then
6664 Nkind (Indic2) /= N_Subtype_Indication
6665 and then Entity (Indic1) = Entity (Indic2);
6667 elsif Nkind (Indic2) /= N_Subtype_Indication then
6669 Nkind (Indic1) /= N_Subtype_Indication
6670 and then Entity (Indic1) = Entity (Indic2);
6673 if Entity (Subtype_Mark (Indic1)) /=
6674 Entity (Subtype_Mark (Indic2))
6679 Elt1 := First (Constraints (Constraint (Indic1)));
6680 Elt2 := First (Constraints (Constraint (Indic2)));
6681 while Present (Elt1) and then Present (Elt2) loop
6682 if not FCE (Elt1, Elt2) then
6695 when N_Attribute_Reference =>
6697 Attribute_Name (E1) = Attribute_Name (E2)
6698 and then FCL (Expressions (E1), Expressions (E2));
6702 Entity (E1) = Entity (E2)
6703 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
6704 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
6706 when N_Short_Circuit | N_Membership_Test =>
6708 FCE (Left_Opnd (E1), Left_Opnd (E2))
6710 FCE (Right_Opnd (E1), Right_Opnd (E2));
6712 when N_Case_Expression =>
6718 if not FCE (Expression (E1), Expression (E2)) then
6722 Alt1 := First (Alternatives (E1));
6723 Alt2 := First (Alternatives (E2));
6725 if Present (Alt1) /= Present (Alt2) then
6727 elsif No (Alt1) then
6731 if not FCE (Expression (Alt1), Expression (Alt2))
6732 or else not FCL (Discrete_Choices (Alt1),
6733 Discrete_Choices (Alt2))
6744 when N_Character_Literal =>
6746 Char_Literal_Value (E1) = Char_Literal_Value (E2);
6748 when N_Component_Association =>
6750 FCL (Choices (E1), Choices (E2))
6752 FCE (Expression (E1), Expression (E2));
6754 when N_Conditional_Expression =>
6756 FCL (Expressions (E1), Expressions (E2));
6758 when N_Explicit_Dereference =>
6760 FCE (Prefix (E1), Prefix (E2));
6762 when N_Extension_Aggregate =>
6764 FCL (Expressions (E1), Expressions (E2))
6765 and then Null_Record_Present (E1) =
6766 Null_Record_Present (E2)
6767 and then FCL (Component_Associations (E1),
6768 Component_Associations (E2));
6770 when N_Function_Call =>
6772 FCE (Name (E1), Name (E2))
6774 FCL (Parameter_Associations (E1),
6775 Parameter_Associations (E2));
6777 when N_Indexed_Component =>
6779 FCE (Prefix (E1), Prefix (E2))
6781 FCL (Expressions (E1), Expressions (E2));
6783 when N_Integer_Literal =>
6784 return (Intval (E1) = Intval (E2));
6789 when N_Operator_Symbol =>
6791 Chars (E1) = Chars (E2);
6793 when N_Others_Choice =>
6796 when N_Parameter_Association =>
6798 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
6799 and then FCE (Explicit_Actual_Parameter (E1),
6800 Explicit_Actual_Parameter (E2));
6802 when N_Qualified_Expression =>
6804 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
6806 FCE (Expression (E1), Expression (E2));
6808 when N_Quantified_Expression =>
6809 if not FCE (Condition (E1), Condition (E2)) then
6813 if Present (Loop_Parameter_Specification (E1))
6814 and then Present (Loop_Parameter_Specification (E2))
6817 L1 : constant Node_Id :=
6818 Loop_Parameter_Specification (E1);
6819 L2 : constant Node_Id :=
6820 Loop_Parameter_Specification (E2);
6824 Reverse_Present (L1) = Reverse_Present (L2)
6826 FCE (Defining_Identifier (L1),
6827 Defining_Identifier (L2))
6829 FCE (Discrete_Subtype_Definition (L1),
6830 Discrete_Subtype_Definition (L2));
6833 else -- quantified expression with an iterator
6835 I1 : constant Node_Id := Iterator_Specification (E1);
6836 I2 : constant Node_Id := Iterator_Specification (E2);
6840 FCE (Defining_Identifier (I1),
6841 Defining_Identifier (I2))
6843 Of_Present (I1) = Of_Present (I2)
6845 Reverse_Present (I1) = Reverse_Present (I2)
6846 and then FCE (Name (I1), Name (I2))
6847 and then FCE (Subtype_Indication (I1),
6848 Subtype_Indication (I2));
6854 FCE (Low_Bound (E1), Low_Bound (E2))
6856 FCE (High_Bound (E1), High_Bound (E2));
6858 when N_Real_Literal =>
6859 return (Realval (E1) = Realval (E2));
6861 when N_Selected_Component =>
6863 FCE (Prefix (E1), Prefix (E2))
6865 FCE (Selector_Name (E1), Selector_Name (E2));
6869 FCE (Prefix (E1), Prefix (E2))
6871 FCE (Discrete_Range (E1), Discrete_Range (E2));
6873 when N_String_Literal =>
6875 S1 : constant String_Id := Strval (E1);
6876 S2 : constant String_Id := Strval (E2);
6877 L1 : constant Nat := String_Length (S1);
6878 L2 : constant Nat := String_Length (S2);
6885 for J in 1 .. L1 loop
6886 if Get_String_Char (S1, J) /=
6887 Get_String_Char (S2, J)
6897 when N_Type_Conversion =>
6899 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
6901 FCE (Expression (E1), Expression (E2));
6905 Entity (E1) = Entity (E2)
6907 FCE (Right_Opnd (E1), Right_Opnd (E2));
6909 when N_Unchecked_Type_Conversion =>
6911 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
6913 FCE (Expression (E1), Expression (E2));
6915 -- All other node types cannot appear in this context. Strictly
6916 -- we should raise a fatal internal error. Instead we just ignore
6917 -- the nodes. This means that if anyone makes a mistake in the
6918 -- expander and mucks an expression tree irretrievably, the
6919 -- result will be a failure to detect a (probably very obscure)
6920 -- case of non-conformance, which is better than bombing on some
6921 -- case where two expressions do in fact conform.
6928 end Fully_Conformant_Expressions;
6930 ----------------------------------------
6931 -- Fully_Conformant_Discrete_Subtypes --
6932 ----------------------------------------
6934 function Fully_Conformant_Discrete_Subtypes
6935 (Given_S1 : Node_Id;
6936 Given_S2 : Node_Id) return Boolean
6938 S1 : constant Node_Id := Original_Node (Given_S1);
6939 S2 : constant Node_Id := Original_Node (Given_S2);
6941 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
6942 -- Special-case for a bound given by a discriminant, which in the body
6943 -- is replaced with the discriminal of the enclosing type.
6945 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
6946 -- Check both bounds
6948 -----------------------
6949 -- Conforming_Bounds --
6950 -----------------------
6952 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
6954 if Is_Entity_Name (B1)
6955 and then Is_Entity_Name (B2)
6956 and then Ekind (Entity (B1)) = E_Discriminant
6958 return Chars (B1) = Chars (B2);
6961 return Fully_Conformant_Expressions (B1, B2);
6963 end Conforming_Bounds;
6965 -----------------------
6966 -- Conforming_Ranges --
6967 -----------------------
6969 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
6972 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
6974 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
6975 end Conforming_Ranges;
6977 -- Start of processing for Fully_Conformant_Discrete_Subtypes
6980 if Nkind (S1) /= Nkind (S2) then
6983 elsif Is_Entity_Name (S1) then
6984 return Entity (S1) = Entity (S2);
6986 elsif Nkind (S1) = N_Range then
6987 return Conforming_Ranges (S1, S2);
6989 elsif Nkind (S1) = N_Subtype_Indication then
6991 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
6994 (Range_Expression (Constraint (S1)),
6995 Range_Expression (Constraint (S2)));
6999 end Fully_Conformant_Discrete_Subtypes;
7001 --------------------
7002 -- Install_Entity --
7003 --------------------
7005 procedure Install_Entity (E : Entity_Id) is
7006 Prev : constant Entity_Id := Current_Entity (E);
7008 Set_Is_Immediately_Visible (E);
7009 Set_Current_Entity (E);
7010 Set_Homonym (E, Prev);
7013 ---------------------
7014 -- Install_Formals --
7015 ---------------------
7017 procedure Install_Formals (Id : Entity_Id) is
7020 F := First_Formal (Id);
7021 while Present (F) loop
7025 end Install_Formals;
7027 -----------------------------
7028 -- Is_Interface_Conformant --
7029 -----------------------------
7031 function Is_Interface_Conformant
7032 (Tagged_Type : Entity_Id;
7033 Iface_Prim : Entity_Id;
7034 Prim : Entity_Id) return Boolean
7036 Iface : constant Entity_Id := Find_Dispatching_Type (Iface_Prim);
7037 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
7040 pragma Assert (Is_Subprogram (Iface_Prim)
7041 and then Is_Subprogram (Prim)
7042 and then Is_Dispatching_Operation (Iface_Prim)
7043 and then Is_Dispatching_Operation (Prim));
7045 pragma Assert (Is_Interface (Iface)
7046 or else (Present (Alias (Iface_Prim))
7049 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
7051 if Prim = Iface_Prim
7052 or else not Is_Subprogram (Prim)
7053 or else Ekind (Prim) /= Ekind (Iface_Prim)
7054 or else not Is_Dispatching_Operation (Prim)
7055 or else Scope (Prim) /= Scope (Tagged_Type)
7057 or else Base_Type (Typ) /= Tagged_Type
7058 or else not Primitive_Names_Match (Iface_Prim, Prim)
7062 -- Case of a procedure, or a function that does not have a controlling
7063 -- result (I or access I).
7065 elsif Ekind (Iface_Prim) = E_Procedure
7066 or else Etype (Prim) = Etype (Iface_Prim)
7067 or else not Has_Controlling_Result (Prim)
7069 return Type_Conformant
7070 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
7072 -- Case of a function returning an interface, or an access to one.
7073 -- Check that the return types correspond.
7075 elsif Implements_Interface (Typ, Iface) then
7076 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
7078 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
7083 Type_Conformant (Prim, Iface_Prim,
7084 Skip_Controlling_Formals => True);
7090 end Is_Interface_Conformant;
7092 ---------------------------------
7093 -- Is_Non_Overriding_Operation --
7094 ---------------------------------
7096 function Is_Non_Overriding_Operation
7097 (Prev_E : Entity_Id;
7098 New_E : Entity_Id) return Boolean
7102 G_Typ : Entity_Id := Empty;
7104 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
7105 -- If F_Type is a derived type associated with a generic actual subtype,
7106 -- then return its Generic_Parent_Type attribute, else return Empty.
7108 function Types_Correspond
7109 (P_Type : Entity_Id;
7110 N_Type : Entity_Id) return Boolean;
7111 -- Returns true if and only if the types (or designated types in the
7112 -- case of anonymous access types) are the same or N_Type is derived
7113 -- directly or indirectly from P_Type.
7115 -----------------------------
7116 -- Get_Generic_Parent_Type --
7117 -----------------------------
7119 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
7124 if Is_Derived_Type (F_Typ)
7125 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
7127 -- The tree must be traversed to determine the parent subtype in
7128 -- the generic unit, which unfortunately isn't always available
7129 -- via semantic attributes. ??? (Note: The use of Original_Node
7130 -- is needed for cases where a full derived type has been
7133 Indic := Subtype_Indication
7134 (Type_Definition (Original_Node (Parent (F_Typ))));
7136 if Nkind (Indic) = N_Subtype_Indication then
7137 G_Typ := Entity (Subtype_Mark (Indic));
7139 G_Typ := Entity (Indic);
7142 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
7143 and then Present (Generic_Parent_Type (Parent (G_Typ)))
7145 return Generic_Parent_Type (Parent (G_Typ));
7150 end Get_Generic_Parent_Type;
7152 ----------------------
7153 -- Types_Correspond --
7154 ----------------------
7156 function Types_Correspond
7157 (P_Type : Entity_Id;
7158 N_Type : Entity_Id) return Boolean
7160 Prev_Type : Entity_Id := Base_Type (P_Type);
7161 New_Type : Entity_Id := Base_Type (N_Type);
7164 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
7165 Prev_Type := Designated_Type (Prev_Type);
7168 if Ekind (New_Type) = E_Anonymous_Access_Type then
7169 New_Type := Designated_Type (New_Type);
7172 if Prev_Type = New_Type then
7175 elsif not Is_Class_Wide_Type (New_Type) then
7176 while Etype (New_Type) /= New_Type loop
7177 New_Type := Etype (New_Type);
7178 if New_Type = Prev_Type then
7184 end Types_Correspond;
7186 -- Start of processing for Is_Non_Overriding_Operation
7189 -- In the case where both operations are implicit derived subprograms
7190 -- then neither overrides the other. This can only occur in certain
7191 -- obscure cases (e.g., derivation from homographs created in a generic
7194 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
7197 elsif Ekind (Current_Scope) = E_Package
7198 and then Is_Generic_Instance (Current_Scope)
7199 and then In_Private_Part (Current_Scope)
7200 and then Comes_From_Source (New_E)
7202 -- We examine the formals and result subtype of the inherited
7203 -- operation, to determine whether their type is derived from (the
7204 -- instance of) a generic type.
7206 Formal := First_Formal (Prev_E);
7207 while Present (Formal) loop
7208 F_Typ := Base_Type (Etype (Formal));
7210 if Ekind (F_Typ) = E_Anonymous_Access_Type then
7211 F_Typ := Designated_Type (F_Typ);
7214 G_Typ := Get_Generic_Parent_Type (F_Typ);
7216 Next_Formal (Formal);
7219 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
7220 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
7227 -- If the generic type is a private type, then the original operation
7228 -- was not overriding in the generic, because there was no primitive
7229 -- operation to override.
7231 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
7232 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
7233 N_Formal_Private_Type_Definition
7237 -- The generic parent type is the ancestor of a formal derived
7238 -- type declaration. We need to check whether it has a primitive
7239 -- operation that should be overridden by New_E in the generic.
7243 P_Formal : Entity_Id;
7244 N_Formal : Entity_Id;
7248 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
7251 while Present (Prim_Elt) loop
7252 P_Prim := Node (Prim_Elt);
7254 if Chars (P_Prim) = Chars (New_E)
7255 and then Ekind (P_Prim) = Ekind (New_E)
7257 P_Formal := First_Formal (P_Prim);
7258 N_Formal := First_Formal (New_E);
7259 while Present (P_Formal) and then Present (N_Formal) loop
7260 P_Typ := Etype (P_Formal);
7261 N_Typ := Etype (N_Formal);
7263 if not Types_Correspond (P_Typ, N_Typ) then
7267 Next_Entity (P_Formal);
7268 Next_Entity (N_Formal);
7271 -- Found a matching primitive operation belonging to the
7272 -- formal ancestor type, so the new subprogram is
7276 and then No (N_Formal)
7277 and then (Ekind (New_E) /= E_Function
7280 (Etype (P_Prim), Etype (New_E)))
7286 Next_Elmt (Prim_Elt);
7289 -- If no match found, then the new subprogram does not
7290 -- override in the generic (nor in the instance).
7298 end Is_Non_Overriding_Operation;
7300 -------------------------------------
7301 -- List_Inherited_Pre_Post_Aspects --
7302 -------------------------------------
7304 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
7306 if Opt.List_Inherited_Aspects
7307 and then (Is_Subprogram (E) or else Is_Generic_Subprogram (E))
7310 Inherited : constant Subprogram_List :=
7311 Inherited_Subprograms (E);
7315 for J in Inherited'Range loop
7316 P := Spec_PPC_List (Contract (Inherited (J)));
7318 while Present (P) loop
7319 Error_Msg_Sloc := Sloc (P);
7321 if Class_Present (P) and then not Split_PPC (P) then
7322 if Pragma_Name (P) = Name_Precondition then
7324 ("?info: & inherits `Pre''Class` aspect from #", E);
7327 ("?info: & inherits `Post''Class` aspect from #", E);
7331 P := Next_Pragma (P);
7336 end List_Inherited_Pre_Post_Aspects;
7338 ------------------------------
7339 -- Make_Inequality_Operator --
7340 ------------------------------
7342 -- S is the defining identifier of an equality operator. We build a
7343 -- subprogram declaration with the right signature. This operation is
7344 -- intrinsic, because it is always expanded as the negation of the
7345 -- call to the equality function.
7347 procedure Make_Inequality_Operator (S : Entity_Id) is
7348 Loc : constant Source_Ptr := Sloc (S);
7351 Op_Name : Entity_Id;
7353 FF : constant Entity_Id := First_Formal (S);
7354 NF : constant Entity_Id := Next_Formal (FF);
7357 -- Check that equality was properly defined, ignore call if not
7364 A : constant Entity_Id :=
7365 Make_Defining_Identifier (Sloc (FF),
7366 Chars => Chars (FF));
7368 B : constant Entity_Id :=
7369 Make_Defining_Identifier (Sloc (NF),
7370 Chars => Chars (NF));
7373 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
7375 Formals := New_List (
7376 Make_Parameter_Specification (Loc,
7377 Defining_Identifier => A,
7379 New_Reference_To (Etype (First_Formal (S)),
7380 Sloc (Etype (First_Formal (S))))),
7382 Make_Parameter_Specification (Loc,
7383 Defining_Identifier => B,
7385 New_Reference_To (Etype (Next_Formal (First_Formal (S))),
7386 Sloc (Etype (Next_Formal (First_Formal (S)))))));
7389 Make_Subprogram_Declaration (Loc,
7391 Make_Function_Specification (Loc,
7392 Defining_Unit_Name => Op_Name,
7393 Parameter_Specifications => Formals,
7394 Result_Definition =>
7395 New_Reference_To (Standard_Boolean, Loc)));
7397 -- Insert inequality right after equality if it is explicit or after
7398 -- the derived type when implicit. These entities are created only
7399 -- for visibility purposes, and eventually replaced in the course of
7400 -- expansion, so they do not need to be attached to the tree and seen
7401 -- by the back-end. Keeping them internal also avoids spurious
7402 -- freezing problems. The declaration is inserted in the tree for
7403 -- analysis, and removed afterwards. If the equality operator comes
7404 -- from an explicit declaration, attach the inequality immediately
7405 -- after. Else the equality is inherited from a derived type
7406 -- declaration, so insert inequality after that declaration.
7408 if No (Alias (S)) then
7409 Insert_After (Unit_Declaration_Node (S), Decl);
7410 elsif Is_List_Member (Parent (S)) then
7411 Insert_After (Parent (S), Decl);
7413 Insert_After (Parent (Etype (First_Formal (S))), Decl);
7416 Mark_Rewrite_Insertion (Decl);
7417 Set_Is_Intrinsic_Subprogram (Op_Name);
7420 Set_Has_Completion (Op_Name);
7421 Set_Corresponding_Equality (Op_Name, S);
7422 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
7424 end Make_Inequality_Operator;
7426 ----------------------
7427 -- May_Need_Actuals --
7428 ----------------------
7430 procedure May_Need_Actuals (Fun : Entity_Id) is
7435 F := First_Formal (Fun);
7437 while Present (F) loop
7438 if No (Default_Value (F)) then
7446 Set_Needs_No_Actuals (Fun, B);
7447 end May_Need_Actuals;
7449 ---------------------
7450 -- Mode_Conformant --
7451 ---------------------
7453 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
7456 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
7458 end Mode_Conformant;
7460 ---------------------------
7461 -- New_Overloaded_Entity --
7462 ---------------------------
7464 procedure New_Overloaded_Entity
7466 Derived_Type : Entity_Id := Empty)
7468 Overridden_Subp : Entity_Id := Empty;
7469 -- Set if the current scope has an operation that is type-conformant
7470 -- with S, and becomes hidden by S.
7472 Is_Primitive_Subp : Boolean;
7473 -- Set to True if the new subprogram is primitive
7476 -- Entity that S overrides
7478 Prev_Vis : Entity_Id := Empty;
7479 -- Predecessor of E in Homonym chain
7481 procedure Check_For_Primitive_Subprogram
7482 (Is_Primitive : out Boolean;
7483 Is_Overriding : Boolean := False);
7484 -- If the subprogram being analyzed is a primitive operation of the type
7485 -- of a formal or result, set the Has_Primitive_Operations flag on the
7486 -- type, and set Is_Primitive to True (otherwise set to False). Set the
7487 -- corresponding flag on the entity itself for later use.
7489 procedure Check_Synchronized_Overriding
7490 (Def_Id : Entity_Id;
7491 Overridden_Subp : out Entity_Id);
7492 -- First determine if Def_Id is an entry or a subprogram either defined
7493 -- in the scope of a task or protected type, or is a primitive of such
7494 -- a type. Check whether Def_Id overrides a subprogram of an interface
7495 -- implemented by the synchronized type, return the overridden entity
7498 function Is_Private_Declaration (E : Entity_Id) return Boolean;
7499 -- Check that E is declared in the private part of the current package,
7500 -- or in the package body, where it may hide a previous declaration.
7501 -- We can't use In_Private_Part by itself because this flag is also
7502 -- set when freezing entities, so we must examine the place of the
7503 -- declaration in the tree, and recognize wrapper packages as well.
7505 function Is_Overriding_Alias
7507 New_E : Entity_Id) return Boolean;
7508 -- Check whether new subprogram and old subprogram are both inherited
7509 -- from subprograms that have distinct dispatch table entries. This can
7510 -- occur with derivations from instances with accidental homonyms.
7511 -- The function is conservative given that the converse is only true
7512 -- within instances that contain accidental overloadings.
7514 ------------------------------------
7515 -- Check_For_Primitive_Subprogram --
7516 ------------------------------------
7518 procedure Check_For_Primitive_Subprogram
7519 (Is_Primitive : out Boolean;
7520 Is_Overriding : Boolean := False)
7526 function Visible_Part_Type (T : Entity_Id) return Boolean;
7527 -- Returns true if T is declared in the visible part of the current
7528 -- package scope; otherwise returns false. Assumes that T is declared
7531 procedure Check_Private_Overriding (T : Entity_Id);
7532 -- Checks that if a primitive abstract subprogram of a visible
7533 -- abstract type is declared in a private part, then it must override
7534 -- an abstract subprogram declared in the visible part. Also checks
7535 -- that if a primitive function with a controlling result is declared
7536 -- in a private part, then it must override a function declared in
7537 -- the visible part.
7539 ------------------------------
7540 -- Check_Private_Overriding --
7541 ------------------------------
7543 procedure Check_Private_Overriding (T : Entity_Id) is
7545 if Is_Package_Or_Generic_Package (Current_Scope)
7546 and then In_Private_Part (Current_Scope)
7547 and then Visible_Part_Type (T)
7548 and then not In_Instance
7550 if Is_Abstract_Type (T)
7551 and then Is_Abstract_Subprogram (S)
7552 and then (not Is_Overriding
7553 or else not Is_Abstract_Subprogram (E))
7556 ("abstract subprograms must be visible "
7557 & "(RM 3.9.3(10))!", S);
7559 elsif Ekind (S) = E_Function
7560 and then not Is_Overriding
7562 if Is_Tagged_Type (T)
7563 and then T = Base_Type (Etype (S))
7566 ("private function with tagged result must"
7567 & " override visible-part function", S);
7569 ("\move subprogram to the visible part"
7570 & " (RM 3.9.3(10))", S);
7572 -- AI05-0073: extend this test to the case of a function
7573 -- with a controlling access result.
7575 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
7576 and then Is_Tagged_Type (Designated_Type (Etype (S)))
7578 not Is_Class_Wide_Type (Designated_Type (Etype (S)))
7579 and then Ada_Version >= Ada_2012
7582 ("private function with controlling access result "
7583 & "must override visible-part function", S);
7585 ("\move subprogram to the visible part"
7586 & " (RM 3.9.3(10))", S);
7590 end Check_Private_Overriding;
7592 -----------------------
7593 -- Visible_Part_Type --
7594 -----------------------
7596 function Visible_Part_Type (T : Entity_Id) return Boolean is
7597 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
7601 -- If the entity is a private type, then it must be declared in a
7604 if Ekind (T) in Private_Kind then
7608 -- Otherwise, we traverse the visible part looking for its
7609 -- corresponding declaration. We cannot use the declaration
7610 -- node directly because in the private part the entity of a
7611 -- private type is the one in the full view, which does not
7612 -- indicate that it is the completion of something visible.
7614 N := First (Visible_Declarations (Specification (P)));
7615 while Present (N) loop
7616 if Nkind (N) = N_Full_Type_Declaration
7617 and then Present (Defining_Identifier (N))
7618 and then T = Defining_Identifier (N)
7622 elsif Nkind_In (N, N_Private_Type_Declaration,
7623 N_Private_Extension_Declaration)
7624 and then Present (Defining_Identifier (N))
7625 and then T = Full_View (Defining_Identifier (N))
7634 end Visible_Part_Type;
7636 -- Start of processing for Check_For_Primitive_Subprogram
7639 Is_Primitive := False;
7641 if not Comes_From_Source (S) then
7644 -- If subprogram is at library level, it is not primitive operation
7646 elsif Current_Scope = Standard_Standard then
7649 elsif (Is_Package_Or_Generic_Package (Current_Scope)
7650 and then not In_Package_Body (Current_Scope))
7651 or else Is_Overriding
7653 -- For function, check return type
7655 if Ekind (S) = E_Function then
7656 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
7657 F_Typ := Designated_Type (Etype (S));
7662 B_Typ := Base_Type (F_Typ);
7664 if Scope (B_Typ) = Current_Scope
7665 and then not Is_Class_Wide_Type (B_Typ)
7666 and then not Is_Generic_Type (B_Typ)
7668 Is_Primitive := True;
7669 Set_Has_Primitive_Operations (B_Typ);
7670 Set_Is_Primitive (S);
7671 Check_Private_Overriding (B_Typ);
7675 -- For all subprograms, check formals
7677 Formal := First_Formal (S);
7678 while Present (Formal) loop
7679 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
7680 F_Typ := Designated_Type (Etype (Formal));
7682 F_Typ := Etype (Formal);
7685 B_Typ := Base_Type (F_Typ);
7687 if Ekind (B_Typ) = E_Access_Subtype then
7688 B_Typ := Base_Type (B_Typ);
7691 if Scope (B_Typ) = Current_Scope
7692 and then not Is_Class_Wide_Type (B_Typ)
7693 and then not Is_Generic_Type (B_Typ)
7695 Is_Primitive := True;
7696 Set_Is_Primitive (S);
7697 Set_Has_Primitive_Operations (B_Typ);
7698 Check_Private_Overriding (B_Typ);
7701 Next_Formal (Formal);
7704 end Check_For_Primitive_Subprogram;
7706 -----------------------------------
7707 -- Check_Synchronized_Overriding --
7708 -----------------------------------
7710 procedure Check_Synchronized_Overriding
7711 (Def_Id : Entity_Id;
7712 Overridden_Subp : out Entity_Id)
7714 Ifaces_List : Elist_Id;
7718 function Matches_Prefixed_View_Profile
7719 (Prim_Params : List_Id;
7720 Iface_Params : List_Id) return Boolean;
7721 -- Determine whether a subprogram's parameter profile Prim_Params
7722 -- matches that of a potentially overridden interface subprogram
7723 -- Iface_Params. Also determine if the type of first parameter of
7724 -- Iface_Params is an implemented interface.
7726 -----------------------------------
7727 -- Matches_Prefixed_View_Profile --
7728 -----------------------------------
7730 function Matches_Prefixed_View_Profile
7731 (Prim_Params : List_Id;
7732 Iface_Params : List_Id) return Boolean
7734 Iface_Id : Entity_Id;
7735 Iface_Param : Node_Id;
7736 Iface_Typ : Entity_Id;
7737 Prim_Id : Entity_Id;
7738 Prim_Param : Node_Id;
7739 Prim_Typ : Entity_Id;
7741 function Is_Implemented
7742 (Ifaces_List : Elist_Id;
7743 Iface : Entity_Id) return Boolean;
7744 -- Determine if Iface is implemented by the current task or
7747 --------------------
7748 -- Is_Implemented --
7749 --------------------
7751 function Is_Implemented
7752 (Ifaces_List : Elist_Id;
7753 Iface : Entity_Id) return Boolean
7755 Iface_Elmt : Elmt_Id;
7758 Iface_Elmt := First_Elmt (Ifaces_List);
7759 while Present (Iface_Elmt) loop
7760 if Node (Iface_Elmt) = Iface then
7764 Next_Elmt (Iface_Elmt);
7770 -- Start of processing for Matches_Prefixed_View_Profile
7773 Iface_Param := First (Iface_Params);
7774 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
7776 if Is_Access_Type (Iface_Typ) then
7777 Iface_Typ := Designated_Type (Iface_Typ);
7780 Prim_Param := First (Prim_Params);
7782 -- The first parameter of the potentially overridden subprogram
7783 -- must be an interface implemented by Prim.
7785 if not Is_Interface (Iface_Typ)
7786 or else not Is_Implemented (Ifaces_List, Iface_Typ)
7791 -- The checks on the object parameters are done, move onto the
7792 -- rest of the parameters.
7794 if not In_Scope then
7795 Prim_Param := Next (Prim_Param);
7798 Iface_Param := Next (Iface_Param);
7799 while Present (Iface_Param) and then Present (Prim_Param) loop
7800 Iface_Id := Defining_Identifier (Iface_Param);
7801 Iface_Typ := Find_Parameter_Type (Iface_Param);
7803 Prim_Id := Defining_Identifier (Prim_Param);
7804 Prim_Typ := Find_Parameter_Type (Prim_Param);
7806 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
7807 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
7808 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
7810 Iface_Typ := Designated_Type (Iface_Typ);
7811 Prim_Typ := Designated_Type (Prim_Typ);
7814 -- Case of multiple interface types inside a parameter profile
7816 -- (Obj_Param : in out Iface; ...; Param : Iface)
7818 -- If the interface type is implemented, then the matching type
7819 -- in the primitive should be the implementing record type.
7821 if Ekind (Iface_Typ) = E_Record_Type
7822 and then Is_Interface (Iface_Typ)
7823 and then Is_Implemented (Ifaces_List, Iface_Typ)
7825 if Prim_Typ /= Typ then
7829 -- The two parameters must be both mode and subtype conformant
7831 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
7833 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
7842 -- One of the two lists contains more parameters than the other
7844 if Present (Iface_Param) or else Present (Prim_Param) then
7849 end Matches_Prefixed_View_Profile;
7851 -- Start of processing for Check_Synchronized_Overriding
7854 Overridden_Subp := Empty;
7856 -- Def_Id must be an entry or a subprogram. We should skip predefined
7857 -- primitives internally generated by the frontend; however at this
7858 -- stage predefined primitives are still not fully decorated. As a
7859 -- minor optimization we skip here internally generated subprograms.
7861 if (Ekind (Def_Id) /= E_Entry
7862 and then Ekind (Def_Id) /= E_Function
7863 and then Ekind (Def_Id) /= E_Procedure)
7864 or else not Comes_From_Source (Def_Id)
7869 -- Search for the concurrent declaration since it contains the list
7870 -- of all implemented interfaces. In this case, the subprogram is
7871 -- declared within the scope of a protected or a task type.
7873 if Present (Scope (Def_Id))
7874 and then Is_Concurrent_Type (Scope (Def_Id))
7875 and then not Is_Generic_Actual_Type (Scope (Def_Id))
7877 Typ := Scope (Def_Id);
7880 -- The enclosing scope is not a synchronized type and the subprogram
7883 elsif No (First_Formal (Def_Id)) then
7886 -- The subprogram has formals and hence it may be a primitive of a
7890 Typ := Etype (First_Formal (Def_Id));
7892 if Is_Access_Type (Typ) then
7893 Typ := Directly_Designated_Type (Typ);
7896 if Is_Concurrent_Type (Typ)
7897 and then not Is_Generic_Actual_Type (Typ)
7901 -- This case occurs when the concurrent type is declared within
7902 -- a generic unit. As a result the corresponding record has been
7903 -- built and used as the type of the first formal, we just have
7904 -- to retrieve the corresponding concurrent type.
7906 elsif Is_Concurrent_Record_Type (Typ)
7907 and then Present (Corresponding_Concurrent_Type (Typ))
7909 Typ := Corresponding_Concurrent_Type (Typ);
7917 -- There is no overriding to check if is an inherited operation in a
7918 -- type derivation on for a generic actual.
7920 Collect_Interfaces (Typ, Ifaces_List);
7922 if Is_Empty_Elmt_List (Ifaces_List) then
7926 -- Determine whether entry or subprogram Def_Id overrides a primitive
7927 -- operation that belongs to one of the interfaces in Ifaces_List.
7930 Candidate : Entity_Id := Empty;
7931 Hom : Entity_Id := Empty;
7932 Iface_Typ : Entity_Id;
7933 Subp : Entity_Id := Empty;
7936 -- Traverse the homonym chain, looking for a potentially
7937 -- overridden subprogram that belongs to an implemented
7940 Hom := Current_Entity_In_Scope (Def_Id);
7941 while Present (Hom) loop
7945 or else not Is_Overloadable (Subp)
7946 or else not Is_Primitive (Subp)
7947 or else not Is_Dispatching_Operation (Subp)
7948 or else not Present (Find_Dispatching_Type (Subp))
7949 or else not Is_Interface (Find_Dispatching_Type (Subp))
7953 -- Entries and procedures can override abstract or null
7954 -- interface procedures.
7956 elsif (Ekind (Def_Id) = E_Procedure
7957 or else Ekind (Def_Id) = E_Entry)
7958 and then Ekind (Subp) = E_Procedure
7959 and then Matches_Prefixed_View_Profile
7960 (Parameter_Specifications (Parent (Def_Id)),
7961 Parameter_Specifications (Parent (Subp)))
7965 -- For an overridden subprogram Subp, check whether the mode
7966 -- of its first parameter is correct depending on the kind
7967 -- of synchronized type.
7970 Formal : constant Node_Id := First_Formal (Candidate);
7973 -- In order for an entry or a protected procedure to
7974 -- override, the first parameter of the overridden
7975 -- routine must be of mode "out", "in out" or
7976 -- access-to-variable.
7978 if (Ekind (Candidate) = E_Entry
7979 or else Ekind (Candidate) = E_Procedure)
7980 and then Is_Protected_Type (Typ)
7981 and then Ekind (Formal) /= E_In_Out_Parameter
7982 and then Ekind (Formal) /= E_Out_Parameter
7983 and then Nkind (Parameter_Type (Parent (Formal)))
7984 /= N_Access_Definition
7988 -- All other cases are OK since a task entry or routine
7989 -- does not have a restriction on the mode of the first
7990 -- parameter of the overridden interface routine.
7993 Overridden_Subp := Candidate;
7998 -- Functions can override abstract interface functions
8000 elsif Ekind (Def_Id) = E_Function
8001 and then Ekind (Subp) = E_Function
8002 and then Matches_Prefixed_View_Profile
8003 (Parameter_Specifications (Parent (Def_Id)),
8004 Parameter_Specifications (Parent (Subp)))
8005 and then Etype (Result_Definition (Parent (Def_Id))) =
8006 Etype (Result_Definition (Parent (Subp)))
8008 Overridden_Subp := Subp;
8012 Hom := Homonym (Hom);
8015 -- After examining all candidates for overriding, we are left with
8016 -- the best match which is a mode incompatible interface routine.
8017 -- Do not emit an error if the Expander is active since this error
8018 -- will be detected later on after all concurrent types are
8019 -- expanded and all wrappers are built. This check is meant for
8020 -- spec-only compilations.
8022 if Present (Candidate) and then not Expander_Active then
8024 Find_Parameter_Type (Parent (First_Formal (Candidate)));
8026 -- Def_Id is primitive of a protected type, declared inside the
8027 -- type, and the candidate is primitive of a limited or
8028 -- synchronized interface.
8031 and then Is_Protected_Type (Typ)
8033 (Is_Limited_Interface (Iface_Typ)
8034 or else Is_Protected_Interface (Iface_Typ)
8035 or else Is_Synchronized_Interface (Iface_Typ)
8036 or else Is_Task_Interface (Iface_Typ))
8039 ("first formal of & must be of mode `OUT`, `IN OUT`"
8040 & " or access-to-variable", Typ, Candidate);
8042 ("\in order to be overridden by protected procedure or "
8043 & "entry (RM 9.4(11.9/2))", Typ);
8047 Overridden_Subp := Candidate;
8050 end Check_Synchronized_Overriding;
8052 ----------------------------
8053 -- Is_Private_Declaration --
8054 ----------------------------
8056 function Is_Private_Declaration (E : Entity_Id) return Boolean is
8057 Priv_Decls : List_Id;
8058 Decl : constant Node_Id := Unit_Declaration_Node (E);
8061 if Is_Package_Or_Generic_Package (Current_Scope)
8062 and then In_Private_Part (Current_Scope)
8065 Private_Declarations (
8066 Specification (Unit_Declaration_Node (Current_Scope)));
8068 return In_Package_Body (Current_Scope)
8070 (Is_List_Member (Decl)
8071 and then List_Containing (Decl) = Priv_Decls)
8072 or else (Nkind (Parent (Decl)) = N_Package_Specification
8075 (Defining_Entity (Parent (Decl)))
8076 and then List_Containing (Parent (Parent (Decl)))
8081 end Is_Private_Declaration;
8083 --------------------------
8084 -- Is_Overriding_Alias --
8085 --------------------------
8087 function Is_Overriding_Alias
8089 New_E : Entity_Id) return Boolean
8091 AO : constant Entity_Id := Alias (Old_E);
8092 AN : constant Entity_Id := Alias (New_E);
8095 return Scope (AO) /= Scope (AN)
8096 or else No (DTC_Entity (AO))
8097 or else No (DTC_Entity (AN))
8098 or else DT_Position (AO) = DT_Position (AN);
8099 end Is_Overriding_Alias;
8101 -- Start of processing for New_Overloaded_Entity
8104 -- We need to look for an entity that S may override. This must be a
8105 -- homonym in the current scope, so we look for the first homonym of
8106 -- S in the current scope as the starting point for the search.
8108 E := Current_Entity_In_Scope (S);
8110 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
8111 -- They are directly added to the list of primitive operations of
8112 -- Derived_Type, unless this is a rederivation in the private part
8113 -- of an operation that was already derived in the visible part of
8114 -- the current package.
8116 if Ada_Version >= Ada_2005
8117 and then Present (Derived_Type)
8118 and then Present (Alias (S))
8119 and then Is_Dispatching_Operation (Alias (S))
8120 and then Present (Find_Dispatching_Type (Alias (S)))
8121 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
8123 -- For private types, when the full-view is processed we propagate to
8124 -- the full view the non-overridden entities whose attribute "alias"
8125 -- references an interface primitive. These entities were added by
8126 -- Derive_Subprograms to ensure that interface primitives are
8129 -- Inside_Freeze_Actions is non zero when S corresponds with an
8130 -- internal entity that links an interface primitive with its
8131 -- covering primitive through attribute Interface_Alias (see
8132 -- Add_Internal_Interface_Entities).
8134 if Inside_Freezing_Actions = 0
8135 and then Is_Package_Or_Generic_Package (Current_Scope)
8136 and then In_Private_Part (Current_Scope)
8137 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
8138 and then Nkind (Parent (S)) = N_Full_Type_Declaration
8139 and then Full_View (Defining_Identifier (Parent (E)))
8140 = Defining_Identifier (Parent (S))
8141 and then Alias (E) = Alias (S)
8143 Check_Operation_From_Private_View (S, E);
8144 Set_Is_Dispatching_Operation (S);
8149 Enter_Overloaded_Entity (S);
8150 Check_Dispatching_Operation (S, Empty);
8151 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
8157 -- If there is no homonym then this is definitely not overriding
8160 Enter_Overloaded_Entity (S);
8161 Check_Dispatching_Operation (S, Empty);
8162 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
8164 -- If subprogram has an explicit declaration, check whether it
8165 -- has an overriding indicator.
8167 if Comes_From_Source (S) then
8168 Check_Synchronized_Overriding (S, Overridden_Subp);
8170 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
8171 -- it may have overridden some hidden inherited primitive. Update
8172 -- Overridden_Subp to avoid spurious errors when checking the
8173 -- overriding indicator.
8175 if Ada_Version >= Ada_2012
8176 and then No (Overridden_Subp)
8177 and then Is_Dispatching_Operation (S)
8178 and then Present (Overridden_Operation (S))
8180 Overridden_Subp := Overridden_Operation (S);
8183 Check_Overriding_Indicator
8184 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
8187 -- If there is a homonym that is not overloadable, then we have an
8188 -- error, except for the special cases checked explicitly below.
8190 elsif not Is_Overloadable (E) then
8192 -- Check for spurious conflict produced by a subprogram that has the
8193 -- same name as that of the enclosing generic package. The conflict
8194 -- occurs within an instance, between the subprogram and the renaming
8195 -- declaration for the package. After the subprogram, the package
8196 -- renaming declaration becomes hidden.
8198 if Ekind (E) = E_Package
8199 and then Present (Renamed_Object (E))
8200 and then Renamed_Object (E) = Current_Scope
8201 and then Nkind (Parent (Renamed_Object (E))) =
8202 N_Package_Specification
8203 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
8206 Set_Is_Immediately_Visible (E, False);
8207 Enter_Overloaded_Entity (S);
8208 Set_Homonym (S, Homonym (E));
8209 Check_Dispatching_Operation (S, Empty);
8210 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
8212 -- If the subprogram is implicit it is hidden by the previous
8213 -- declaration. However if it is dispatching, it must appear in the
8214 -- dispatch table anyway, because it can be dispatched to even if it
8215 -- cannot be called directly.
8217 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
8218 Set_Scope (S, Current_Scope);
8220 if Is_Dispatching_Operation (Alias (S)) then
8221 Check_Dispatching_Operation (S, Empty);
8227 Error_Msg_Sloc := Sloc (E);
8229 -- Generate message, with useful additional warning if in generic
8231 if Is_Generic_Unit (E) then
8232 Error_Msg_N ("previous generic unit cannot be overloaded", S);
8233 Error_Msg_N ("\& conflicts with declaration#", S);
8235 Error_Msg_N ("& conflicts with declaration#", S);
8241 -- E exists and is overloadable
8244 Check_Synchronized_Overriding (S, Overridden_Subp);
8246 -- Loop through E and its homonyms to determine if any of them is
8247 -- the candidate for overriding by S.
8249 while Present (E) loop
8251 -- Definitely not interesting if not in the current scope
8253 if Scope (E) /= Current_Scope then
8256 -- Check if we have type conformance
8258 elsif Type_Conformant (E, S) then
8260 -- If the old and new entities have the same profile and one
8261 -- is not the body of the other, then this is an error, unless
8262 -- one of them is implicitly declared.
8264 -- There are some cases when both can be implicit, for example
8265 -- when both a literal and a function that overrides it are
8266 -- inherited in a derivation, or when an inherited operation
8267 -- of a tagged full type overrides the inherited operation of
8268 -- a private extension. Ada 83 had a special rule for the
8269 -- literal case. In Ada95, the later implicit operation hides
8270 -- the former, and the literal is always the former. In the
8271 -- odd case where both are derived operations declared at the
8272 -- same point, both operations should be declared, and in that
8273 -- case we bypass the following test and proceed to the next
8274 -- part. This can only occur for certain obscure cases in
8275 -- instances, when an operation on a type derived from a formal
8276 -- private type does not override a homograph inherited from
8277 -- the actual. In subsequent derivations of such a type, the
8278 -- DT positions of these operations remain distinct, if they
8281 if Present (Alias (S))
8282 and then (No (Alias (E))
8283 or else Comes_From_Source (E)
8284 or else Is_Abstract_Subprogram (S)
8286 (Is_Dispatching_Operation (E)
8287 and then Is_Overriding_Alias (E, S)))
8288 and then Ekind (E) /= E_Enumeration_Literal
8290 -- When an derived operation is overloaded it may be due to
8291 -- the fact that the full view of a private extension
8292 -- re-inherits. It has to be dealt with.
8294 if Is_Package_Or_Generic_Package (Current_Scope)
8295 and then In_Private_Part (Current_Scope)
8297 Check_Operation_From_Private_View (S, E);
8300 -- In any case the implicit operation remains hidden by the
8301 -- existing declaration, which is overriding. Indicate that
8302 -- E overrides the operation from which S is inherited.
8304 if Present (Alias (S)) then
8305 Set_Overridden_Operation (E, Alias (S));
8307 Set_Overridden_Operation (E, S);
8310 if Comes_From_Source (E) then
8311 Check_Overriding_Indicator (E, S, Is_Primitive => False);
8316 -- Within an instance, the renaming declarations for actual
8317 -- subprograms may become ambiguous, but they do not hide each
8320 elsif Ekind (E) /= E_Entry
8321 and then not Comes_From_Source (E)
8322 and then not Is_Generic_Instance (E)
8323 and then (Present (Alias (E))
8324 or else Is_Intrinsic_Subprogram (E))
8325 and then (not In_Instance
8326 or else No (Parent (E))
8327 or else Nkind (Unit_Declaration_Node (E)) /=
8328 N_Subprogram_Renaming_Declaration)
8330 -- A subprogram child unit is not allowed to override an
8331 -- inherited subprogram (10.1.1(20)).
8333 if Is_Child_Unit (S) then
8335 ("child unit overrides inherited subprogram in parent",
8340 if Is_Non_Overriding_Operation (E, S) then
8341 Enter_Overloaded_Entity (S);
8343 if No (Derived_Type)
8344 or else Is_Tagged_Type (Derived_Type)
8346 Check_Dispatching_Operation (S, Empty);
8352 -- E is a derived operation or an internal operator which
8353 -- is being overridden. Remove E from further visibility.
8354 -- Furthermore, if E is a dispatching operation, it must be
8355 -- replaced in the list of primitive operations of its type
8356 -- (see Override_Dispatching_Operation).
8358 Overridden_Subp := E;
8364 Prev := First_Entity (Current_Scope);
8365 while Present (Prev)
8366 and then Next_Entity (Prev) /= E
8371 -- It is possible for E to be in the current scope and
8372 -- yet not in the entity chain. This can only occur in a
8373 -- generic context where E is an implicit concatenation
8374 -- in the formal part, because in a generic body the
8375 -- entity chain starts with the formals.
8378 (Present (Prev) or else Chars (E) = Name_Op_Concat);
8380 -- E must be removed both from the entity_list of the
8381 -- current scope, and from the visibility chain
8383 if Debug_Flag_E then
8384 Write_Str ("Override implicit operation ");
8385 Write_Int (Int (E));
8389 -- If E is a predefined concatenation, it stands for four
8390 -- different operations. As a result, a single explicit
8391 -- declaration does not hide it. In a possible ambiguous
8392 -- situation, Disambiguate chooses the user-defined op,
8393 -- so it is correct to retain the previous internal one.
8395 if Chars (E) /= Name_Op_Concat
8396 or else Ekind (E) /= E_Operator
8398 -- For nondispatching derived operations that are
8399 -- overridden by a subprogram declared in the private
8400 -- part of a package, we retain the derived subprogram
8401 -- but mark it as not immediately visible. If the
8402 -- derived operation was declared in the visible part
8403 -- then this ensures that it will still be visible
8404 -- outside the package with the proper signature
8405 -- (calls from outside must also be directed to this
8406 -- version rather than the overriding one, unlike the
8407 -- dispatching case). Calls from inside the package
8408 -- will still resolve to the overriding subprogram
8409 -- since the derived one is marked as not visible
8410 -- within the package.
8412 -- If the private operation is dispatching, we achieve
8413 -- the overriding by keeping the implicit operation
8414 -- but setting its alias to be the overriding one. In
8415 -- this fashion the proper body is executed in all
8416 -- cases, but the original signature is used outside
8419 -- If the overriding is not in the private part, we
8420 -- remove the implicit operation altogether.
8422 if Is_Private_Declaration (S) then
8423 if not Is_Dispatching_Operation (E) then
8424 Set_Is_Immediately_Visible (E, False);
8426 -- Work done in Override_Dispatching_Operation,
8427 -- so nothing else need to be done here.
8433 -- Find predecessor of E in Homonym chain
8435 if E = Current_Entity (E) then
8438 Prev_Vis := Current_Entity (E);
8439 while Homonym (Prev_Vis) /= E loop
8440 Prev_Vis := Homonym (Prev_Vis);
8444 if Prev_Vis /= Empty then
8446 -- Skip E in the visibility chain
8448 Set_Homonym (Prev_Vis, Homonym (E));
8451 Set_Name_Entity_Id (Chars (E), Homonym (E));
8454 Set_Next_Entity (Prev, Next_Entity (E));
8456 if No (Next_Entity (Prev)) then
8457 Set_Last_Entity (Current_Scope, Prev);
8462 Enter_Overloaded_Entity (S);
8464 -- For entities generated by Derive_Subprograms the
8465 -- overridden operation is the inherited primitive
8466 -- (which is available through the attribute alias).
8468 if not (Comes_From_Source (E))
8469 and then Is_Dispatching_Operation (E)
8470 and then Find_Dispatching_Type (E) =
8471 Find_Dispatching_Type (S)
8472 and then Present (Alias (E))
8473 and then Comes_From_Source (Alias (E))
8475 Set_Overridden_Operation (S, Alias (E));
8477 -- Normal case of setting entity as overridden
8479 -- Note: Static_Initialization and Overridden_Operation
8480 -- attributes use the same field in subprogram entities.
8481 -- Static_Initialization is only defined for internal
8482 -- initialization procedures, where Overridden_Operation
8483 -- is irrelevant. Therefore the setting of this attribute
8484 -- must check whether the target is an init_proc.
8486 elsif not Is_Init_Proc (S) then
8487 Set_Overridden_Operation (S, E);
8490 Check_Overriding_Indicator (S, E, Is_Primitive => True);
8492 -- If S is a user-defined subprogram or a null procedure
8493 -- expanded to override an inherited null procedure, or a
8494 -- predefined dispatching primitive then indicate that E
8495 -- overrides the operation from which S is inherited.
8497 if Comes_From_Source (S)
8499 (Present (Parent (S))
8501 Nkind (Parent (S)) = N_Procedure_Specification
8503 Null_Present (Parent (S)))
8505 (Present (Alias (E))
8507 Is_Predefined_Dispatching_Operation (Alias (E)))
8509 if Present (Alias (E)) then
8510 Set_Overridden_Operation (S, Alias (E));
8514 if Is_Dispatching_Operation (E) then
8516 -- An overriding dispatching subprogram inherits the
8517 -- convention of the overridden subprogram (AI-117).
8519 Set_Convention (S, Convention (E));
8520 Check_Dispatching_Operation (S, E);
8523 Check_Dispatching_Operation (S, Empty);
8526 Check_For_Primitive_Subprogram
8527 (Is_Primitive_Subp, Is_Overriding => True);
8528 goto Check_Inequality;
8531 -- Apparent redeclarations in instances can occur when two
8532 -- formal types get the same actual type. The subprograms in
8533 -- in the instance are legal, even if not callable from the
8534 -- outside. Calls from within are disambiguated elsewhere.
8535 -- For dispatching operations in the visible part, the usual
8536 -- rules apply, and operations with the same profile are not
8539 elsif (In_Instance_Visible_Part
8540 and then not Is_Dispatching_Operation (E))
8541 or else In_Instance_Not_Visible
8545 -- Here we have a real error (identical profile)
8548 Error_Msg_Sloc := Sloc (E);
8550 -- Avoid cascaded errors if the entity appears in
8551 -- subsequent calls.
8553 Set_Scope (S, Current_Scope);
8555 -- Generate error, with extra useful warning for the case
8556 -- of a generic instance with no completion.
8558 if Is_Generic_Instance (S)
8559 and then not Has_Completion (E)
8562 ("instantiation cannot provide body for&", S);
8563 Error_Msg_N ("\& conflicts with declaration#", S);
8565 Error_Msg_N ("& conflicts with declaration#", S);
8572 -- If one subprogram has an access parameter and the other
8573 -- a parameter of an access type, calls to either might be
8574 -- ambiguous. Verify that parameters match except for the
8575 -- access parameter.
8577 if May_Hide_Profile then
8583 F1 := First_Formal (S);
8584 F2 := First_Formal (E);
8585 while Present (F1) and then Present (F2) loop
8586 if Is_Access_Type (Etype (F1)) then
8587 if not Is_Access_Type (Etype (F2))
8588 or else not Conforming_Types
8589 (Designated_Type (Etype (F1)),
8590 Designated_Type (Etype (F2)),
8593 May_Hide_Profile := False;
8597 not Conforming_Types
8598 (Etype (F1), Etype (F2), Type_Conformant)
8600 May_Hide_Profile := False;
8611 Error_Msg_NE ("calls to& may be ambiguous?", S, S);
8620 -- On exit, we know that S is a new entity
8622 Enter_Overloaded_Entity (S);
8623 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
8624 Check_Overriding_Indicator
8625 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
8627 -- Overloading is not allowed in SPARK, except for operators
8629 if Nkind (S) /= N_Defining_Operator_Symbol then
8630 Error_Msg_Sloc := Sloc (Homonym (S));
8631 Check_SPARK_Restriction
8632 ("overloading not allowed with entity#", S);
8635 -- If S is a derived operation for an untagged type then by
8636 -- definition it's not a dispatching operation (even if the parent
8637 -- operation was dispatching), so Check_Dispatching_Operation is not
8638 -- called in that case.
8640 if No (Derived_Type)
8641 or else Is_Tagged_Type (Derived_Type)
8643 Check_Dispatching_Operation (S, Empty);
8647 -- If this is a user-defined equality operator that is not a derived
8648 -- subprogram, create the corresponding inequality. If the operation is
8649 -- dispatching, the expansion is done elsewhere, and we do not create
8650 -- an explicit inequality operation.
8652 <<Check_Inequality>>
8653 if Chars (S) = Name_Op_Eq
8654 and then Etype (S) = Standard_Boolean
8655 and then Present (Parent (S))
8656 and then not Is_Dispatching_Operation (S)
8658 Make_Inequality_Operator (S);
8660 if Ada_Version >= Ada_2012 then
8661 Check_Untagged_Equality (S);
8664 end New_Overloaded_Entity;
8666 ---------------------
8667 -- Process_Formals --
8668 ---------------------
8670 procedure Process_Formals
8672 Related_Nod : Node_Id)
8674 Param_Spec : Node_Id;
8676 Formal_Type : Entity_Id;
8680 Num_Out_Params : Nat := 0;
8681 First_Out_Param : Entity_Id := Empty;
8682 -- Used for setting Is_Only_Out_Parameter
8684 function Designates_From_With_Type (Typ : Entity_Id) return Boolean;
8685 -- Determine whether an access type designates a type coming from a
8688 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
8689 -- Check whether the default has a class-wide type. After analysis the
8690 -- default has the type of the formal, so we must also check explicitly
8691 -- for an access attribute.
8693 -------------------------------
8694 -- Designates_From_With_Type --
8695 -------------------------------
8697 function Designates_From_With_Type (Typ : Entity_Id) return Boolean is
8698 Desig : Entity_Id := Typ;
8701 if Is_Access_Type (Desig) then
8702 Desig := Directly_Designated_Type (Desig);
8705 if Is_Class_Wide_Type (Desig) then
8706 Desig := Root_Type (Desig);
8710 Ekind (Desig) = E_Incomplete_Type
8711 and then From_With_Type (Desig);
8712 end Designates_From_With_Type;
8714 ---------------------------
8715 -- Is_Class_Wide_Default --
8716 ---------------------------
8718 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
8720 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
8721 or else (Nkind (D) = N_Attribute_Reference
8722 and then Attribute_Name (D) = Name_Access
8723 and then Is_Class_Wide_Type (Etype (Prefix (D))));
8724 end Is_Class_Wide_Default;
8726 -- Start of processing for Process_Formals
8729 -- In order to prevent premature use of the formals in the same formal
8730 -- part, the Ekind is left undefined until all default expressions are
8731 -- analyzed. The Ekind is established in a separate loop at the end.
8733 Param_Spec := First (T);
8734 while Present (Param_Spec) loop
8735 Formal := Defining_Identifier (Param_Spec);
8736 Set_Never_Set_In_Source (Formal, True);
8737 Enter_Name (Formal);
8739 -- Case of ordinary parameters
8741 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
8742 Find_Type (Parameter_Type (Param_Spec));
8743 Ptype := Parameter_Type (Param_Spec);
8745 if Ptype = Error then
8749 Formal_Type := Entity (Ptype);
8751 if Is_Incomplete_Type (Formal_Type)
8753 (Is_Class_Wide_Type (Formal_Type)
8754 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
8756 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
8757 -- primitive operations, as long as their completion is
8758 -- in the same declarative part. If in the private part
8759 -- this means that the type cannot be a Taft-amendment type.
8760 -- Check is done on package exit. For access to subprograms,
8761 -- the use is legal for Taft-amendment types.
8763 if Is_Tagged_Type (Formal_Type) then
8764 if Ekind (Scope (Current_Scope)) = E_Package
8765 and then not From_With_Type (Formal_Type)
8766 and then not Is_Class_Wide_Type (Formal_Type)
8769 (Parent (T), N_Access_Function_Definition,
8770 N_Access_Procedure_Definition)
8774 Private_Dependents (Base_Type (Formal_Type)));
8776 -- Freezing is delayed to ensure that Register_Prim
8777 -- will get called for this operation, which is needed
8778 -- in cases where static dispatch tables aren't built.
8779 -- (Note that the same is done for controlling access
8780 -- parameter cases in function Access_Definition.)
8782 Set_Has_Delayed_Freeze (Current_Scope);
8786 -- Special handling of Value_Type for CIL case
8788 elsif Is_Value_Type (Formal_Type) then
8791 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
8792 N_Access_Procedure_Definition)
8795 -- AI05-0151: Tagged incomplete types are allowed in all
8796 -- formal parts. Untagged incomplete types are not allowed
8799 if Ada_Version >= Ada_2012 then
8800 if Is_Tagged_Type (Formal_Type) then
8803 elsif Nkind_In (Parent (Parent (T)), N_Accept_Statement,
8808 ("invalid use of untagged incomplete type&",
8809 Ptype, Formal_Type);
8814 ("invalid use of incomplete type&",
8815 Param_Spec, Formal_Type);
8817 -- Further checks on the legality of incomplete types
8818 -- in formal parts are delayed until the freeze point
8819 -- of the enclosing subprogram or access to subprogram.
8823 elsif Ekind (Formal_Type) = E_Void then
8825 ("premature use of&",
8826 Parameter_Type (Param_Spec), Formal_Type);
8829 -- Ada 2005 (AI-231): Create and decorate an internal subtype
8830 -- declaration corresponding to the null-excluding type of the
8831 -- formal in the enclosing scope. Finally, replace the parameter
8832 -- type of the formal with the internal subtype.
8834 if Ada_Version >= Ada_2005
8835 and then Null_Exclusion_Present (Param_Spec)
8837 if not Is_Access_Type (Formal_Type) then
8839 ("`NOT NULL` allowed only for an access type", Param_Spec);
8842 if Can_Never_Be_Null (Formal_Type)
8843 and then Comes_From_Source (Related_Nod)
8846 ("`NOT NULL` not allowed (& already excludes null)",
8847 Param_Spec, Formal_Type);
8851 Create_Null_Excluding_Itype
8853 Related_Nod => Related_Nod,
8854 Scope_Id => Scope (Current_Scope));
8856 -- If the designated type of the itype is an itype we
8857 -- decorate it with the Has_Delayed_Freeze attribute to
8858 -- avoid problems with the backend.
8861 -- type T is access procedure;
8862 -- procedure Op (O : not null T);
8864 if Is_Itype (Directly_Designated_Type (Formal_Type)) then
8865 Set_Has_Delayed_Freeze (Formal_Type);
8870 -- An access formal type
8874 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
8876 -- No need to continue if we already notified errors
8878 if not Present (Formal_Type) then
8882 -- Ada 2005 (AI-254)
8885 AD : constant Node_Id :=
8886 Access_To_Subprogram_Definition
8887 (Parameter_Type (Param_Spec));
8889 if Present (AD) and then Protected_Present (AD) then
8891 Replace_Anonymous_Access_To_Protected_Subprogram
8897 Set_Etype (Formal, Formal_Type);
8899 Default := Expression (Param_Spec);
8901 if Present (Default) then
8902 Check_SPARK_Restriction
8903 ("default expression is not allowed", Default);
8905 if Out_Present (Param_Spec) then
8907 ("default initialization only allowed for IN parameters",
8911 -- Do the special preanalysis of the expression (see section on
8912 -- "Handling of Default Expressions" in the spec of package Sem).
8914 Preanalyze_Spec_Expression (Default, Formal_Type);
8916 -- An access to constant cannot be the default for
8917 -- an access parameter that is an access to variable.
8919 if Ekind (Formal_Type) = E_Anonymous_Access_Type
8920 and then not Is_Access_Constant (Formal_Type)
8921 and then Is_Access_Type (Etype (Default))
8922 and then Is_Access_Constant (Etype (Default))
8925 ("formal that is access to variable cannot be initialized " &
8926 "with an access-to-constant expression", Default);
8929 -- Check that the designated type of an access parameter's default
8930 -- is not a class-wide type unless the parameter's designated type
8931 -- is also class-wide.
8933 if Ekind (Formal_Type) = E_Anonymous_Access_Type
8934 and then not Designates_From_With_Type (Formal_Type)
8935 and then Is_Class_Wide_Default (Default)
8936 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
8939 ("access to class-wide expression not allowed here", Default);
8942 -- Check incorrect use of dynamically tagged expressions
8944 if Is_Tagged_Type (Formal_Type) then
8945 Check_Dynamically_Tagged_Expression
8948 Related_Nod => Default);
8952 -- Ada 2005 (AI-231): Static checks
8954 if Ada_Version >= Ada_2005
8955 and then Is_Access_Type (Etype (Formal))
8956 and then Can_Never_Be_Null (Etype (Formal))
8958 Null_Exclusion_Static_Checks (Param_Spec);
8965 -- If this is the formal part of a function specification, analyze the
8966 -- subtype mark in the context where the formals are visible but not
8967 -- yet usable, and may hide outer homographs.
8969 if Nkind (Related_Nod) = N_Function_Specification then
8970 Analyze_Return_Type (Related_Nod);
8973 -- Now set the kind (mode) of each formal
8975 Param_Spec := First (T);
8976 while Present (Param_Spec) loop
8977 Formal := Defining_Identifier (Param_Spec);
8978 Set_Formal_Mode (Formal);
8980 if Ekind (Formal) = E_In_Parameter then
8981 Set_Default_Value (Formal, Expression (Param_Spec));
8983 if Present (Expression (Param_Spec)) then
8984 Default := Expression (Param_Spec);
8986 if Is_Scalar_Type (Etype (Default)) then
8988 (Parameter_Type (Param_Spec)) /= N_Access_Definition
8990 Formal_Type := Entity (Parameter_Type (Param_Spec));
8993 Formal_Type := Access_Definition
8994 (Related_Nod, Parameter_Type (Param_Spec));
8997 Apply_Scalar_Range_Check (Default, Formal_Type);
9001 elsif Ekind (Formal) = E_Out_Parameter then
9002 Num_Out_Params := Num_Out_Params + 1;
9004 if Num_Out_Params = 1 then
9005 First_Out_Param := Formal;
9008 elsif Ekind (Formal) = E_In_Out_Parameter then
9009 Num_Out_Params := Num_Out_Params + 1;
9015 if Present (First_Out_Param) and then Num_Out_Params = 1 then
9016 Set_Is_Only_Out_Parameter (First_Out_Param);
9018 end Process_Formals;
9024 procedure Process_PPCs
9026 Spec_Id : Entity_Id;
9027 Body_Id : Entity_Id)
9029 Loc : constant Source_Ptr := Sloc (N);
9033 Designator : Entity_Id;
9034 -- Subprogram designator, set from Spec_Id if present, else Body_Id
9036 Precond : Node_Id := Empty;
9037 -- Set non-Empty if we prepend precondition to the declarations. This
9038 -- is used to hook up inherited preconditions (adding the condition
9039 -- expression with OR ELSE, and adding the message).
9041 Inherited_Precond : Node_Id;
9042 -- Precondition inherited from parent subprogram
9044 Inherited : constant Subprogram_List :=
9045 Inherited_Subprograms (Spec_Id);
9046 -- List of subprograms inherited by this subprogram
9048 Plist : List_Id := No_List;
9049 -- List of generated postconditions
9051 function Grab_PPC (Pspec : Entity_Id := Empty) return Node_Id;
9052 -- Prag contains an analyzed precondition or postcondition pragma. This
9053 -- function copies the pragma, changes it to the corresponding Check
9054 -- pragma and returns the Check pragma as the result. If Pspec is non-
9055 -- empty, this is the case of inheriting a PPC, where we must change
9056 -- references to parameters of the inherited subprogram to point to the
9057 -- corresponding parameters of the current subprogram.
9059 function Invariants_Or_Predicates_Present return Boolean;
9060 -- Determines if any invariants or predicates are present for any OUT
9061 -- or IN OUT parameters of the subprogram, or (for a function) if the
9062 -- return value has an invariant.
9068 function Grab_PPC (Pspec : Entity_Id := Empty) return Node_Id is
9069 Nam : constant Name_Id := Pragma_Name (Prag);
9074 -- Prepare map if this is the case where we have to map entities of
9075 -- arguments in the overridden subprogram to corresponding entities
9076 -- of the current subprogram.
9087 Map := New_Elmt_List;
9088 PF := First_Formal (Pspec);
9089 CF := First_Formal (Designator);
9090 while Present (PF) loop
9091 Append_Elmt (PF, Map);
9092 Append_Elmt (CF, Map);
9099 -- Now we can copy the tree, doing any required substitutions
9101 CP := New_Copy_Tree (Prag, Map => Map, New_Scope => Current_Scope);
9103 -- Set Analyzed to false, since we want to reanalyze the check
9104 -- procedure. Note that it is only at the outer level that we
9105 -- do this fiddling, for the spec cases, the already preanalyzed
9106 -- parameters are not affected.
9108 Set_Analyzed (CP, False);
9110 -- We also make sure Comes_From_Source is False for the copy
9112 Set_Comes_From_Source (CP, False);
9114 -- For a postcondition pragma within a generic, preserve the pragma
9115 -- for later expansion.
9117 if Nam = Name_Postcondition
9118 and then not Expander_Active
9123 -- Change copy of pragma into corresponding pragma Check
9125 Prepend_To (Pragma_Argument_Associations (CP),
9126 Make_Pragma_Argument_Association (Sloc (Prag),
9127 Expression => Make_Identifier (Loc, Nam)));
9128 Set_Pragma_Identifier (CP, Make_Identifier (Sloc (Prag), Name_Check));
9130 -- If this is inherited case and the current message starts with
9131 -- "failed p", we change it to "failed inherited p...".
9133 if Present (Pspec) then
9135 Msg : constant Node_Id :=
9136 Last (Pragma_Argument_Associations (CP));
9139 if Chars (Msg) = Name_Message then
9140 String_To_Name_Buffer (Strval (Expression (Msg)));
9142 if Name_Buffer (1 .. 8) = "failed p" then
9143 Insert_Str_In_Name_Buffer ("inherited ", 8);
9145 (Expression (Last (Pragma_Argument_Associations (CP))),
9146 String_From_Name_Buffer);
9152 -- Return the check pragma
9157 --------------------------------------
9158 -- Invariants_Or_Predicates_Present --
9159 --------------------------------------
9161 function Invariants_Or_Predicates_Present return Boolean is
9165 -- Check function return result
9167 if Ekind (Designator) /= E_Procedure
9168 and then Has_Invariants (Etype (Designator))
9175 Formal := First_Formal (Designator);
9176 while Present (Formal) loop
9177 if Ekind (Formal) /= E_In_Parameter
9179 (Has_Invariants (Etype (Formal))
9180 or else Present (Predicate_Function (Etype (Formal))))
9185 Next_Formal (Formal);
9189 end Invariants_Or_Predicates_Present;
9191 -- Start of processing for Process_PPCs
9194 -- Capture designator from spec if present, else from body
9196 if Present (Spec_Id) then
9197 Designator := Spec_Id;
9199 Designator := Body_Id;
9202 -- Grab preconditions from spec
9204 if Present (Spec_Id) then
9206 -- Loop through PPC pragmas from spec. Note that preconditions from
9207 -- the body will be analyzed and converted when we scan the body
9208 -- declarations below.
9210 Prag := Spec_PPC_List (Contract (Spec_Id));
9211 while Present (Prag) loop
9212 if Pragma_Name (Prag) = Name_Precondition then
9214 -- For Pre (or Precondition pragma), we simply prepend the
9215 -- pragma to the list of declarations right away so that it
9216 -- will be executed at the start of the procedure. Note that
9217 -- this processing reverses the order of the list, which is
9218 -- what we want since new entries were chained to the head of
9219 -- the list. There can be more than one precondition when we
9220 -- use pragma Precondition.
9222 if not Class_Present (Prag) then
9223 Prepend (Grab_PPC, Declarations (N));
9225 -- For Pre'Class there can only be one pragma, and we save
9226 -- it in Precond for now. We will add inherited Pre'Class
9227 -- stuff before inserting this pragma in the declarations.
9229 Precond := Grab_PPC;
9233 Prag := Next_Pragma (Prag);
9236 -- Now deal with inherited preconditions
9238 for J in Inherited'Range loop
9239 Prag := Spec_PPC_List (Contract (Inherited (J)));
9241 while Present (Prag) loop
9242 if Pragma_Name (Prag) = Name_Precondition
9243 and then Class_Present (Prag)
9245 Inherited_Precond := Grab_PPC (Inherited (J));
9247 -- No precondition so far, so establish this as the first
9249 if No (Precond) then
9250 Precond := Inherited_Precond;
9252 -- Here we already have a precondition, add inherited one
9255 -- Add new precondition to old one using OR ELSE
9258 New_Expr : constant Node_Id :=
9262 (Pragma_Argument_Associations
9263 (Inherited_Precond))));
9264 Old_Expr : constant Node_Id :=
9268 (Pragma_Argument_Associations
9272 if Paren_Count (Old_Expr) = 0 then
9273 Set_Paren_Count (Old_Expr, 1);
9276 if Paren_Count (New_Expr) = 0 then
9277 Set_Paren_Count (New_Expr, 1);
9281 Make_Or_Else (Sloc (Old_Expr),
9282 Left_Opnd => Relocate_Node (Old_Expr),
9283 Right_Opnd => New_Expr));
9286 -- Add new message in the form:
9288 -- failed precondition from bla
9289 -- also failed inherited precondition from bla
9292 -- Skip this if exception locations are suppressed
9294 if not Exception_Locations_Suppressed then
9296 New_Msg : constant Node_Id :=
9299 (Pragma_Argument_Associations
9300 (Inherited_Precond)));
9301 Old_Msg : constant Node_Id :=
9304 (Pragma_Argument_Associations
9307 Start_String (Strval (Old_Msg));
9308 Store_String_Chars (ASCII.LF & " also ");
9309 Store_String_Chars (Strval (New_Msg));
9310 Set_Strval (Old_Msg, End_String);
9316 Prag := Next_Pragma (Prag);
9320 -- If we have built a precondition for Pre'Class (including any
9321 -- Pre'Class aspects inherited from parent subprograms), then we
9322 -- insert this composite precondition at this stage.
9324 if Present (Precond) then
9325 Prepend (Precond, Declarations (N));
9329 -- Build postconditions procedure if needed and prepend the following
9330 -- declaration to the start of the declarations for the subprogram.
9332 -- procedure _postconditions [(_Result : resulttype)] is
9334 -- pragma Check (Postcondition, condition [,message]);
9335 -- pragma Check (Postcondition, condition [,message]);
9337 -- Invariant_Procedure (_Result) ...
9338 -- Invariant_Procedure (Arg1)
9342 -- First we deal with the postconditions in the body
9344 if Is_Non_Empty_List (Declarations (N)) then
9346 -- Loop through declarations
9348 Prag := First (Declarations (N));
9349 while Present (Prag) loop
9350 if Nkind (Prag) = N_Pragma then
9352 -- If pragma, capture if enabled postcondition, else ignore
9354 if Pragma_Name (Prag) = Name_Postcondition
9355 and then Check_Enabled (Name_Postcondition)
9357 if Plist = No_List then
9358 Plist := Empty_List;
9363 -- If expansion is disabled, as in a generic unit, save
9364 -- pragma for later expansion.
9366 if not Expander_Active then
9367 Prepend (Grab_PPC, Declarations (N));
9369 Append (Grab_PPC, Plist);
9375 -- Not a pragma, if comes from source, then end scan
9377 elsif Comes_From_Source (Prag) then
9380 -- Skip stuff not coming from source
9388 -- Now deal with any postconditions from the spec
9390 if Present (Spec_Id) then
9391 Spec_Postconditions : declare
9392 procedure Process_Post_Conditions
9395 -- This processes the Spec_PPC_List from Spec, processing any
9396 -- postconditions from the list. If Class is True, then only
9397 -- postconditions marked with Class_Present are considered.
9398 -- The caller has checked that Spec_PPC_List is non-Empty.
9400 -----------------------------
9401 -- Process_Post_Conditions --
9402 -----------------------------
9404 procedure Process_Post_Conditions
9417 -- Loop through PPC pragmas from spec
9419 Prag := Spec_PPC_List (Contract (Spec));
9421 if Pragma_Name (Prag) = Name_Postcondition
9422 and then (not Class or else Class_Present (Prag))
9424 if Plist = No_List then
9425 Plist := Empty_List;
9428 if not Expander_Active then
9430 (Grab_PPC (Pspec), Declarations (N));
9432 Append (Grab_PPC (Pspec), Plist);
9436 Prag := Next_Pragma (Prag);
9437 exit when No (Prag);
9439 end Process_Post_Conditions;
9441 -- Start of processing for Spec_Postconditions
9444 if Present (Spec_PPC_List (Contract (Spec_Id))) then
9445 Process_Post_Conditions (Spec_Id, Class => False);
9448 -- Process inherited postconditions
9450 for J in Inherited'Range loop
9451 if Present (Spec_PPC_List (Contract (Inherited (J)))) then
9452 Process_Post_Conditions (Inherited (J), Class => True);
9455 end Spec_Postconditions;
9458 -- If we had any postconditions and expansion is enabled, or if the
9459 -- procedure has invariants, then build the _Postconditions procedure.
9461 if (Present (Plist) or else Invariants_Or_Predicates_Present)
9462 and then Expander_Active
9465 Plist := Empty_List;
9468 -- Special processing for function case
9470 if Ekind (Designator) /= E_Procedure then
9472 Rent : constant Entity_Id :=
9473 Make_Defining_Identifier (Loc,
9474 Chars => Name_uResult);
9475 Ftyp : constant Entity_Id := Etype (Designator);
9478 Set_Etype (Rent, Ftyp);
9480 -- Add argument for return
9484 Make_Parameter_Specification (Loc,
9485 Parameter_Type => New_Occurrence_Of (Ftyp, Loc),
9486 Defining_Identifier => Rent));
9488 -- Add invariant call if returning type with invariants
9490 if Has_Invariants (Etype (Rent))
9491 and then Present (Invariant_Procedure (Etype (Rent)))
9494 Make_Invariant_Call (New_Occurrence_Of (Rent, Loc)));
9498 -- Procedure rather than a function
9504 -- Add invariant calls and predicate calls for parameters. Note that
9505 -- this is done for functions as well, since in Ada 2012 they can
9506 -- have IN OUT args.
9513 Formal := First_Formal (Designator);
9514 while Present (Formal) loop
9515 if Ekind (Formal) /= E_In_Parameter then
9516 Ftype := Etype (Formal);
9518 if Has_Invariants (Ftype)
9519 and then Present (Invariant_Procedure (Ftype))
9523 (New_Occurrence_Of (Formal, Loc)));
9526 if Present (Predicate_Function (Ftype)) then
9528 Make_Predicate_Check
9529 (Ftype, New_Occurrence_Of (Formal, Loc)));
9533 Next_Formal (Formal);
9537 -- Build and insert postcondition procedure
9540 Post_Proc : constant Entity_Id :=
9541 Make_Defining_Identifier (Loc,
9542 Chars => Name_uPostconditions);
9543 -- The entity for the _Postconditions procedure
9546 Prepend_To (Declarations (N),
9547 Make_Subprogram_Body (Loc,
9549 Make_Procedure_Specification (Loc,
9550 Defining_Unit_Name => Post_Proc,
9551 Parameter_Specifications => Parms),
9553 Declarations => Empty_List,
9555 Handled_Statement_Sequence =>
9556 Make_Handled_Sequence_Of_Statements (Loc,
9557 Statements => Plist)));
9559 Set_Ekind (Post_Proc, E_Procedure);
9561 -- If this is a procedure, set the Postcondition_Proc attribute on
9562 -- the proper defining entity for the subprogram.
9564 if Ekind (Designator) = E_Procedure then
9565 Set_Postcondition_Proc (Designator, Post_Proc);
9569 Set_Has_Postconditions (Designator);
9573 ----------------------------
9574 -- Reference_Body_Formals --
9575 ----------------------------
9577 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
9582 if Error_Posted (Spec) then
9586 -- Iterate over both lists. They may be of different lengths if the two
9587 -- specs are not conformant.
9589 Fs := First_Formal (Spec);
9590 Fb := First_Formal (Bod);
9591 while Present (Fs) and then Present (Fb) loop
9592 Generate_Reference (Fs, Fb, 'b');
9595 Style.Check_Identifier (Fb, Fs);
9598 Set_Spec_Entity (Fb, Fs);
9599 Set_Referenced (Fs, False);
9603 end Reference_Body_Formals;
9605 -------------------------
9606 -- Set_Actual_Subtypes --
9607 -------------------------
9609 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
9613 First_Stmt : Node_Id := Empty;
9614 AS_Needed : Boolean;
9617 -- If this is an empty initialization procedure, no need to create
9618 -- actual subtypes (small optimization).
9620 if Ekind (Subp) = E_Procedure
9621 and then Is_Null_Init_Proc (Subp)
9626 Formal := First_Formal (Subp);
9627 while Present (Formal) loop
9628 T := Etype (Formal);
9630 -- We never need an actual subtype for a constrained formal
9632 if Is_Constrained (T) then
9635 -- If we have unknown discriminants, then we do not need an actual
9636 -- subtype, or more accurately we cannot figure it out! Note that
9637 -- all class-wide types have unknown discriminants.
9639 elsif Has_Unknown_Discriminants (T) then
9642 -- At this stage we have an unconstrained type that may need an
9643 -- actual subtype. For sure the actual subtype is needed if we have
9644 -- an unconstrained array type.
9646 elsif Is_Array_Type (T) then
9649 -- The only other case needing an actual subtype is an unconstrained
9650 -- record type which is an IN parameter (we cannot generate actual
9651 -- subtypes for the OUT or IN OUT case, since an assignment can
9652 -- change the discriminant values. However we exclude the case of
9653 -- initialization procedures, since discriminants are handled very
9654 -- specially in this context, see the section entitled "Handling of
9655 -- Discriminants" in Einfo.
9657 -- We also exclude the case of Discrim_SO_Functions (functions used
9658 -- in front end layout mode for size/offset values), since in such
9659 -- functions only discriminants are referenced, and not only are such
9660 -- subtypes not needed, but they cannot always be generated, because
9661 -- of order of elaboration issues.
9663 elsif Is_Record_Type (T)
9664 and then Ekind (Formal) = E_In_Parameter
9665 and then Chars (Formal) /= Name_uInit
9666 and then not Is_Unchecked_Union (T)
9667 and then not Is_Discrim_SO_Function (Subp)
9671 -- All other cases do not need an actual subtype
9677 -- Generate actual subtypes for unconstrained arrays and
9678 -- unconstrained discriminated records.
9681 if Nkind (N) = N_Accept_Statement then
9683 -- If expansion is active, The formal is replaced by a local
9684 -- variable that renames the corresponding entry of the
9685 -- parameter block, and it is this local variable that may
9686 -- require an actual subtype.
9688 if Expander_Active then
9689 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
9691 Decl := Build_Actual_Subtype (T, Formal);
9694 if Present (Handled_Statement_Sequence (N)) then
9696 First (Statements (Handled_Statement_Sequence (N)));
9697 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
9698 Mark_Rewrite_Insertion (Decl);
9700 -- If the accept statement has no body, there will be no
9701 -- reference to the actuals, so no need to compute actual
9708 Decl := Build_Actual_Subtype (T, Formal);
9709 Prepend (Decl, Declarations (N));
9710 Mark_Rewrite_Insertion (Decl);
9713 -- The declaration uses the bounds of an existing object, and
9714 -- therefore needs no constraint checks.
9716 Analyze (Decl, Suppress => All_Checks);
9718 -- We need to freeze manually the generated type when it is
9719 -- inserted anywhere else than in a declarative part.
9721 if Present (First_Stmt) then
9722 Insert_List_Before_And_Analyze (First_Stmt,
9723 Freeze_Entity (Defining_Identifier (Decl), N));
9726 if Nkind (N) = N_Accept_Statement
9727 and then Expander_Active
9729 Set_Actual_Subtype (Renamed_Object (Formal),
9730 Defining_Identifier (Decl));
9732 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
9736 Next_Formal (Formal);
9738 end Set_Actual_Subtypes;
9740 ---------------------
9741 -- Set_Formal_Mode --
9742 ---------------------
9744 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
9745 Spec : constant Node_Id := Parent (Formal_Id);
9748 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
9749 -- since we ensure that corresponding actuals are always valid at the
9750 -- point of the call.
9752 if Out_Present (Spec) then
9753 if Ekind (Scope (Formal_Id)) = E_Function
9754 or else Ekind (Scope (Formal_Id)) = E_Generic_Function
9756 -- [IN] OUT parameters allowed for functions in Ada 2012
9758 if Ada_Version >= Ada_2012 then
9759 if In_Present (Spec) then
9760 Set_Ekind (Formal_Id, E_In_Out_Parameter);
9762 Set_Ekind (Formal_Id, E_Out_Parameter);
9765 -- But not in earlier versions of Ada
9768 Error_Msg_N ("functions can only have IN parameters", Spec);
9769 Set_Ekind (Formal_Id, E_In_Parameter);
9772 elsif In_Present (Spec) then
9773 Set_Ekind (Formal_Id, E_In_Out_Parameter);
9776 Set_Ekind (Formal_Id, E_Out_Parameter);
9777 Set_Never_Set_In_Source (Formal_Id, True);
9778 Set_Is_True_Constant (Formal_Id, False);
9779 Set_Current_Value (Formal_Id, Empty);
9783 Set_Ekind (Formal_Id, E_In_Parameter);
9786 -- Set Is_Known_Non_Null for access parameters since the language
9787 -- guarantees that access parameters are always non-null. We also set
9788 -- Can_Never_Be_Null, since there is no way to change the value.
9790 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
9792 -- Ada 2005 (AI-231): In Ada95, access parameters are always non-
9793 -- null; In Ada 2005, only if then null_exclusion is explicit.
9795 if Ada_Version < Ada_2005
9796 or else Can_Never_Be_Null (Etype (Formal_Id))
9798 Set_Is_Known_Non_Null (Formal_Id);
9799 Set_Can_Never_Be_Null (Formal_Id);
9802 -- Ada 2005 (AI-231): Null-exclusion access subtype
9804 elsif Is_Access_Type (Etype (Formal_Id))
9805 and then Can_Never_Be_Null (Etype (Formal_Id))
9807 Set_Is_Known_Non_Null (Formal_Id);
9810 Set_Mechanism (Formal_Id, Default_Mechanism);
9811 Set_Formal_Validity (Formal_Id);
9812 end Set_Formal_Mode;
9814 -------------------------
9815 -- Set_Formal_Validity --
9816 -------------------------
9818 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
9820 -- If no validity checking, then we cannot assume anything about the
9821 -- validity of parameters, since we do not know there is any checking
9822 -- of the validity on the call side.
9824 if not Validity_Checks_On then
9827 -- If validity checking for parameters is enabled, this means we are
9828 -- not supposed to make any assumptions about argument values.
9830 elsif Validity_Check_Parameters then
9833 -- If we are checking in parameters, we will assume that the caller is
9834 -- also checking parameters, so we can assume the parameter is valid.
9836 elsif Ekind (Formal_Id) = E_In_Parameter
9837 and then Validity_Check_In_Params
9839 Set_Is_Known_Valid (Formal_Id, True);
9841 -- Similar treatment for IN OUT parameters
9843 elsif Ekind (Formal_Id) = E_In_Out_Parameter
9844 and then Validity_Check_In_Out_Params
9846 Set_Is_Known_Valid (Formal_Id, True);
9848 end Set_Formal_Validity;
9850 ------------------------
9851 -- Subtype_Conformant --
9852 ------------------------
9854 function Subtype_Conformant
9855 (New_Id : Entity_Id;
9857 Skip_Controlling_Formals : Boolean := False) return Boolean
9861 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
9862 Skip_Controlling_Formals => Skip_Controlling_Formals);
9864 end Subtype_Conformant;
9866 ---------------------
9867 -- Type_Conformant --
9868 ---------------------
9870 function Type_Conformant
9871 (New_Id : Entity_Id;
9873 Skip_Controlling_Formals : Boolean := False) return Boolean
9877 May_Hide_Profile := False;
9880 (New_Id, Old_Id, Type_Conformant, False, Result,
9881 Skip_Controlling_Formals => Skip_Controlling_Formals);
9883 end Type_Conformant;
9885 -------------------------------
9886 -- Valid_Operator_Definition --
9887 -------------------------------
9889 procedure Valid_Operator_Definition (Designator : Entity_Id) is
9892 Id : constant Name_Id := Chars (Designator);
9896 F := First_Formal (Designator);
9897 while Present (F) loop
9900 if Present (Default_Value (F)) then
9902 ("default values not allowed for operator parameters",
9909 -- Verify that user-defined operators have proper number of arguments
9910 -- First case of operators which can only be unary
9913 or else Id = Name_Op_Abs
9917 -- Case of operators which can be unary or binary
9919 elsif Id = Name_Op_Add
9920 or Id = Name_Op_Subtract
9922 N_OK := (N in 1 .. 2);
9924 -- All other operators can only be binary
9932 ("incorrect number of arguments for operator", Designator);
9936 and then Base_Type (Etype (Designator)) = Standard_Boolean
9937 and then not Is_Intrinsic_Subprogram (Designator)
9940 ("explicit definition of inequality not allowed", Designator);
9942 end Valid_Operator_Definition;