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 expand
2344 -- the freeze actions that include the bodies. In particular, extra
2345 -- formals for accessibility or for return-in-place may need to be
2346 -- generated. Freeze nodes, if any, are inserted before the current
2347 -- body. These freeze actions are also needed in ASIS mode to enable
2348 -- the proper back-annotations.
2350 if not Is_Frozen (Spec_Id)
2351 and then (Expander_Active or ASIS_Mode)
2353 -- Force the generation of its freezing node to ensure proper
2354 -- management of access types in the backend.
2356 -- This is definitely needed for some cases, but it is not clear
2357 -- why, to be investigated further???
2359 Set_Has_Delayed_Freeze (Spec_Id);
2360 Freeze_Before (N, Spec_Id);
2364 -- Mark presence of postcondition procedure in current scope and mark
2365 -- the procedure itself as needing debug info. The latter is important
2366 -- when analyzing decision coverage (for example, for MC/DC coverage).
2368 if Chars (Body_Id) = Name_uPostconditions then
2369 Set_Has_Postconditions (Current_Scope);
2370 Set_Debug_Info_Needed (Body_Id);
2373 -- Place subprogram on scope stack, and make formals visible. If there
2374 -- is a spec, the visible entity remains that of the spec.
2376 if Present (Spec_Id) then
2377 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
2379 if Is_Child_Unit (Spec_Id) then
2380 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
2384 Style.Check_Identifier (Body_Id, Spec_Id);
2387 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
2388 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
2390 if Is_Abstract_Subprogram (Spec_Id) then
2391 Error_Msg_N ("an abstract subprogram cannot have a body", N);
2395 Set_Convention (Body_Id, Convention (Spec_Id));
2396 Set_Has_Completion (Spec_Id);
2398 if Is_Protected_Type (Scope (Spec_Id)) then
2399 Prot_Typ := Scope (Spec_Id);
2402 -- If this is a body generated for a renaming, do not check for
2403 -- full conformance. The check is redundant, because the spec of
2404 -- the body is a copy of the spec in the renaming declaration,
2405 -- and the test can lead to spurious errors on nested defaults.
2407 if Present (Spec_Decl)
2408 and then not Comes_From_Source (N)
2410 (Nkind (Original_Node (Spec_Decl)) =
2411 N_Subprogram_Renaming_Declaration
2412 or else (Present (Corresponding_Body (Spec_Decl))
2414 Nkind (Unit_Declaration_Node
2415 (Corresponding_Body (Spec_Decl))) =
2416 N_Subprogram_Renaming_Declaration))
2420 -- Conversely, the spec may have been generated for specless body
2421 -- with an inline pragma.
2423 elsif Comes_From_Source (N)
2424 and then not Comes_From_Source (Spec_Id)
2425 and then Has_Pragma_Inline (Spec_Id)
2432 Fully_Conformant, True, Conformant, Body_Id);
2435 -- If the body is not fully conformant, we have to decide if we
2436 -- should analyze it or not. If it has a really messed up profile
2437 -- then we probably should not analyze it, since we will get too
2438 -- many bogus messages.
2440 -- Our decision is to go ahead in the non-fully conformant case
2441 -- only if it is at least mode conformant with the spec. Note
2442 -- that the call to Check_Fully_Conformant has issued the proper
2443 -- error messages to complain about the lack of conformance.
2446 and then not Mode_Conformant (Body_Id, Spec_Id)
2452 if Spec_Id /= Body_Id then
2453 Reference_Body_Formals (Spec_Id, Body_Id);
2456 if Nkind (N) /= N_Subprogram_Body_Stub then
2457 Set_Corresponding_Spec (N, Spec_Id);
2459 -- Ada 2005 (AI-345): If the operation is a primitive operation
2460 -- of a concurrent type, the type of the first parameter has been
2461 -- replaced with the corresponding record, which is the proper
2462 -- run-time structure to use. However, within the body there may
2463 -- be uses of the formals that depend on primitive operations
2464 -- of the type (in particular calls in prefixed form) for which
2465 -- we need the original concurrent type. The operation may have
2466 -- several controlling formals, so the replacement must be done
2469 if Comes_From_Source (Spec_Id)
2470 and then Present (First_Entity (Spec_Id))
2471 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
2472 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
2474 Present (Interfaces (Etype (First_Entity (Spec_Id))))
2477 (Corresponding_Concurrent_Type
2478 (Etype (First_Entity (Spec_Id))))
2481 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
2485 Form := First_Formal (Spec_Id);
2486 while Present (Form) loop
2487 if Etype (Form) = Typ then
2488 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
2496 -- Make the formals visible, and place subprogram on scope stack.
2497 -- This is also the point at which we set Last_Real_Spec_Entity
2498 -- to mark the entities which will not be moved to the body.
2500 Install_Formals (Spec_Id);
2501 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
2502 Push_Scope (Spec_Id);
2504 -- Make sure that the subprogram is immediately visible. For
2505 -- child units that have no separate spec this is indispensable.
2506 -- Otherwise it is safe albeit redundant.
2508 Set_Is_Immediately_Visible (Spec_Id);
2511 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
2512 Set_Ekind (Body_Id, E_Subprogram_Body);
2513 Set_Scope (Body_Id, Scope (Spec_Id));
2514 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
2516 -- Case of subprogram body with no previous spec
2519 -- Check for style warning required
2523 -- Only apply check for source level subprograms for which checks
2524 -- have not been suppressed.
2526 and then Comes_From_Source (Body_Id)
2527 and then not Suppress_Style_Checks (Body_Id)
2529 -- No warnings within an instance
2531 and then not In_Instance
2533 -- No warnings for expression functions
2535 and then Nkind (Original_Node (N)) /= N_Expression_Function
2537 Style.Body_With_No_Spec (N);
2540 New_Overloaded_Entity (Body_Id);
2542 if Nkind (N) /= N_Subprogram_Body_Stub then
2543 Set_Acts_As_Spec (N);
2544 Generate_Definition (Body_Id);
2545 Set_Contract (Body_Id, Make_Contract (Sloc (Body_Id)));
2547 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
2548 Generate_Reference_To_Formals (Body_Id);
2549 Install_Formals (Body_Id);
2550 Push_Scope (Body_Id);
2554 -- If the return type is an anonymous access type whose designated type
2555 -- is the limited view of a class-wide type and the non-limited view is
2556 -- available, update the return type accordingly.
2558 if Ada_Version >= Ada_2005
2559 and then Comes_From_Source (N)
2566 Rtyp := Etype (Current_Scope);
2568 if Ekind (Rtyp) = E_Anonymous_Access_Type then
2569 Etyp := Directly_Designated_Type (Rtyp);
2571 if Is_Class_Wide_Type (Etyp)
2572 and then From_With_Type (Etyp)
2574 Set_Directly_Designated_Type
2575 (Etype (Current_Scope), Available_View (Etyp));
2581 -- If this is the proper body of a stub, we must verify that the stub
2582 -- conforms to the body, and to the previous spec if one was present.
2583 -- we know already that the body conforms to that spec. This test is
2584 -- only required for subprograms that come from source.
2586 if Nkind (Parent (N)) = N_Subunit
2587 and then Comes_From_Source (N)
2588 and then not Error_Posted (Body_Id)
2589 and then Nkind (Corresponding_Stub (Parent (N))) =
2590 N_Subprogram_Body_Stub
2593 Old_Id : constant Entity_Id :=
2595 (Specification (Corresponding_Stub (Parent (N))));
2597 Conformant : Boolean := False;
2600 if No (Spec_Id) then
2601 Check_Fully_Conformant (Body_Id, Old_Id);
2605 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
2607 if not Conformant then
2609 -- The stub was taken to be a new declaration. Indicate
2610 -- that it lacks a body.
2612 Set_Has_Completion (Old_Id, False);
2618 Set_Has_Completion (Body_Id);
2619 Check_Eliminated (Body_Id);
2621 if Nkind (N) = N_Subprogram_Body_Stub then
2624 elsif Present (Spec_Id)
2625 and then Expander_Active
2627 (Has_Pragma_Inline_Always (Spec_Id)
2628 or else (Has_Pragma_Inline (Spec_Id) and Front_End_Inlining))
2630 Build_Body_To_Inline (N, Spec_Id);
2633 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
2634 -- if its specification we have to install the private withed units.
2635 -- This holds for child units as well.
2637 if Is_Compilation_Unit (Body_Id)
2638 or else Nkind (Parent (N)) = N_Compilation_Unit
2640 Install_Private_With_Clauses (Body_Id);
2643 Check_Anonymous_Return;
2645 -- Set the Protected_Formal field of each extra formal of the protected
2646 -- subprogram to reference the corresponding extra formal of the
2647 -- subprogram that implements it. For regular formals this occurs when
2648 -- the protected subprogram's declaration is expanded, but the extra
2649 -- formals don't get created until the subprogram is frozen. We need to
2650 -- do this before analyzing the protected subprogram's body so that any
2651 -- references to the original subprogram's extra formals will be changed
2652 -- refer to the implementing subprogram's formals (see Expand_Formal).
2654 if Present (Spec_Id)
2655 and then Is_Protected_Type (Scope (Spec_Id))
2656 and then Present (Protected_Body_Subprogram (Spec_Id))
2659 Impl_Subp : constant Entity_Id :=
2660 Protected_Body_Subprogram (Spec_Id);
2661 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
2662 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
2664 while Present (Prot_Ext_Formal) loop
2665 pragma Assert (Present (Impl_Ext_Formal));
2666 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
2667 Next_Formal_With_Extras (Prot_Ext_Formal);
2668 Next_Formal_With_Extras (Impl_Ext_Formal);
2673 -- Now we can go on to analyze the body
2675 HSS := Handled_Statement_Sequence (N);
2676 Set_Actual_Subtypes (N, Current_Scope);
2678 -- Deal with preconditions and postconditions. In formal verification
2679 -- mode, we keep pre- and postconditions attached to entities rather
2680 -- than inserted in the code, in order to facilitate a distinct
2681 -- treatment for them.
2683 if not ALFA_Mode then
2684 Process_PPCs (N, Spec_Id, Body_Id);
2687 -- Add a declaration for the Protection object, renaming declarations
2688 -- for discriminals and privals and finally a declaration for the entry
2689 -- family index (if applicable). This form of early expansion is done
2690 -- when the Expander is active because Install_Private_Data_Declarations
2691 -- references entities which were created during regular expansion.
2694 and then Comes_From_Source (N)
2695 and then Present (Prot_Typ)
2696 and then Present (Spec_Id)
2697 and then not Is_Eliminated (Spec_Id)
2699 Install_Private_Data_Declarations
2700 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
2703 -- Analyze the declarations (this call will analyze the precondition
2704 -- Check pragmas we prepended to the list, as well as the declaration
2705 -- of the _Postconditions procedure).
2707 Analyze_Declarations (Declarations (N));
2709 -- Check completion, and analyze the statements
2712 Inspect_Deferred_Constant_Completion (Declarations (N));
2715 -- Deal with end of scope processing for the body
2717 Process_End_Label (HSS, 't', Current_Scope);
2719 Check_Subprogram_Order (N);
2720 Set_Analyzed (Body_Id);
2722 -- If we have a separate spec, then the analysis of the declarations
2723 -- caused the entities in the body to be chained to the spec id, but
2724 -- we want them chained to the body id. Only the formal parameters
2725 -- end up chained to the spec id in this case.
2727 if Present (Spec_Id) then
2729 -- We must conform to the categorization of our spec
2731 Validate_Categorization_Dependency (N, Spec_Id);
2733 -- And if this is a child unit, the parent units must conform
2735 if Is_Child_Unit (Spec_Id) then
2736 Validate_Categorization_Dependency
2737 (Unit_Declaration_Node (Spec_Id), Spec_Id);
2740 -- Here is where we move entities from the spec to the body
2742 -- Case where there are entities that stay with the spec
2744 if Present (Last_Real_Spec_Entity) then
2746 -- No body entities (happens when the only real spec entities
2747 -- come from precondition and postcondition pragmas)
2749 if No (Last_Entity (Body_Id)) then
2751 (Body_Id, Next_Entity (Last_Real_Spec_Entity));
2753 -- Body entities present (formals), so chain stuff past them
2757 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
2760 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
2761 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
2762 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
2764 -- Case where there are no spec entities, in this case there can
2765 -- be no body entities either, so just move everything.
2768 pragma Assert (No (Last_Entity (Body_Id)));
2769 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
2770 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
2771 Set_First_Entity (Spec_Id, Empty);
2772 Set_Last_Entity (Spec_Id, Empty);
2776 Check_Missing_Return;
2778 -- Now we are going to check for variables that are never modified in
2779 -- the body of the procedure. But first we deal with a special case
2780 -- where we want to modify this check. If the body of the subprogram
2781 -- starts with a raise statement or its equivalent, or if the body
2782 -- consists entirely of a null statement, then it is pretty obvious
2783 -- that it is OK to not reference the parameters. For example, this
2784 -- might be the following common idiom for a stubbed function:
2785 -- statement of the procedure raises an exception. In particular this
2786 -- deals with the common idiom of a stubbed function, which might
2787 -- appear as something like
2789 -- function F (A : Integer) return Some_Type;
2792 -- raise Program_Error;
2796 -- Here the purpose of X is simply to satisfy the annoying requirement
2797 -- in Ada that there be at least one return, and we certainly do not
2798 -- want to go posting warnings on X that it is not initialized! On
2799 -- the other hand, if X is entirely unreferenced that should still
2802 -- What we do is to detect these cases, and if we find them, flag the
2803 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
2804 -- suppress unwanted warnings. For the case of the function stub above
2805 -- we have a special test to set X as apparently assigned to suppress
2812 -- Skip initial labels (for one thing this occurs when we are in
2813 -- front end ZCX mode, but in any case it is irrelevant), and also
2814 -- initial Push_xxx_Error_Label nodes, which are also irrelevant.
2816 Stm := First (Statements (HSS));
2817 while Nkind (Stm) = N_Label
2818 or else Nkind (Stm) in N_Push_xxx_Label
2823 -- Do the test on the original statement before expansion
2826 Ostm : constant Node_Id := Original_Node (Stm);
2829 -- If explicit raise statement, turn on flag
2831 if Nkind (Ostm) = N_Raise_Statement then
2832 Set_Trivial_Subprogram (Stm);
2834 -- If null statement, and no following statements, turn on flag
2836 elsif Nkind (Stm) = N_Null_Statement
2837 and then Comes_From_Source (Stm)
2838 and then No (Next (Stm))
2840 Set_Trivial_Subprogram (Stm);
2842 -- Check for explicit call cases which likely raise an exception
2844 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
2845 if Is_Entity_Name (Name (Ostm)) then
2847 Ent : constant Entity_Id := Entity (Name (Ostm));
2850 -- If the procedure is marked No_Return, then likely it
2851 -- raises an exception, but in any case it is not coming
2852 -- back here, so turn on the flag.
2855 and then Ekind (Ent) = E_Procedure
2856 and then No_Return (Ent)
2858 Set_Trivial_Subprogram (Stm);
2866 -- Check for variables that are never modified
2872 -- If there is a separate spec, then transfer Never_Set_In_Source
2873 -- flags from out parameters to the corresponding entities in the
2874 -- body. The reason we do that is we want to post error flags on
2875 -- the body entities, not the spec entities.
2877 if Present (Spec_Id) then
2878 E1 := First_Entity (Spec_Id);
2879 while Present (E1) loop
2880 if Ekind (E1) = E_Out_Parameter then
2881 E2 := First_Entity (Body_Id);
2882 while Present (E2) loop
2883 exit when Chars (E1) = Chars (E2);
2887 if Present (E2) then
2888 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
2896 -- Check references in body unless it was deleted. Note that the
2897 -- check of Body_Deleted here is not just for efficiency, it is
2898 -- necessary to avoid junk warnings on formal parameters.
2900 if not Body_Deleted then
2901 Check_References (Body_Id);
2904 end Analyze_Subprogram_Body_Helper;
2906 ------------------------------------
2907 -- Analyze_Subprogram_Declaration --
2908 ------------------------------------
2910 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
2911 Loc : constant Source_Ptr := Sloc (N);
2912 Scop : constant Entity_Id := Current_Scope;
2913 Designator : Entity_Id;
2915 Null_Body : Node_Id := Empty;
2917 -- Start of processing for Analyze_Subprogram_Declaration
2920 -- Null procedures are not allowed in SPARK
2922 if Nkind (Specification (N)) = N_Procedure_Specification
2923 and then Null_Present (Specification (N))
2925 Check_SPARK_Restriction ("null procedure is not allowed", N);
2928 -- For a null procedure, capture the profile before analysis, for
2929 -- expansion at the freeze point and at each point of call. The body
2930 -- will only be used if the procedure has preconditions. In that case
2931 -- the body is analyzed at the freeze point.
2933 if Nkind (Specification (N)) = N_Procedure_Specification
2934 and then Null_Present (Specification (N))
2935 and then Expander_Active
2938 Make_Subprogram_Body (Loc,
2940 New_Copy_Tree (Specification (N)),
2943 Handled_Statement_Sequence =>
2944 Make_Handled_Sequence_Of_Statements (Loc,
2945 Statements => New_List (Make_Null_Statement (Loc))));
2947 -- Create new entities for body and formals
2949 Set_Defining_Unit_Name (Specification (Null_Body),
2950 Make_Defining_Identifier (Loc, Chars (Defining_Entity (N))));
2951 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
2953 Form := First (Parameter_Specifications (Specification (Null_Body)));
2954 while Present (Form) loop
2955 Set_Defining_Identifier (Form,
2956 Make_Defining_Identifier (Loc,
2957 Chars (Defining_Identifier (Form))));
2959 -- Resolve the types of the formals now, because the freeze point
2960 -- may appear in a different context, e.g. an instantiation.
2962 if Nkind (Parameter_Type (Form)) /= N_Access_Definition then
2963 Find_Type (Parameter_Type (Form));
2966 No (Access_To_Subprogram_Definition (Parameter_Type (Form)))
2968 Find_Type (Subtype_Mark (Parameter_Type (Form)));
2972 -- the case of a null procedure with a formal that is an
2973 -- access_to_subprogram type, and that is used as an actual
2974 -- in an instantiation is left to the enthusiastic reader.
2982 if Is_Protected_Type (Current_Scope) then
2983 Error_Msg_N ("protected operation cannot be a null procedure", N);
2987 Designator := Analyze_Subprogram_Specification (Specification (N));
2988 Generate_Definition (Designator);
2989 -- ??? why this call, already in Analyze_Subprogram_Specification
2991 if Debug_Flag_C then
2992 Write_Str ("==> subprogram spec ");
2993 Write_Name (Chars (Designator));
2994 Write_Str (" from ");
2995 Write_Location (Sloc (N));
3000 if Nkind (Specification (N)) = N_Procedure_Specification
3001 and then Null_Present (Specification (N))
3003 Set_Has_Completion (Designator);
3005 if Present (Null_Body) then
3006 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
3007 Set_Body_To_Inline (N, Null_Body);
3008 Set_Is_Inlined (Designator);
3012 Validate_RCI_Subprogram_Declaration (N);
3013 New_Overloaded_Entity (Designator);
3014 Check_Delayed_Subprogram (Designator);
3016 -- If the type of the first formal of the current subprogram is a
3017 -- nongeneric tagged private type, mark the subprogram as being a
3018 -- private primitive. Ditto if this is a function with controlling
3019 -- result, and the return type is currently private. In both cases,
3020 -- the type of the controlling argument or result must be in the
3021 -- current scope for the operation to be primitive.
3023 if Has_Controlling_Result (Designator)
3024 and then Is_Private_Type (Etype (Designator))
3025 and then Scope (Etype (Designator)) = Current_Scope
3026 and then not Is_Generic_Actual_Type (Etype (Designator))
3028 Set_Is_Private_Primitive (Designator);
3030 elsif Present (First_Formal (Designator)) then
3032 Formal_Typ : constant Entity_Id :=
3033 Etype (First_Formal (Designator));
3035 Set_Is_Private_Primitive (Designator,
3036 Is_Tagged_Type (Formal_Typ)
3037 and then Scope (Formal_Typ) = Current_Scope
3038 and then Is_Private_Type (Formal_Typ)
3039 and then not Is_Generic_Actual_Type (Formal_Typ));
3043 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
3046 if Ada_Version >= Ada_2005
3047 and then Comes_From_Source (N)
3048 and then Is_Dispatching_Operation (Designator)
3055 if Has_Controlling_Result (Designator) then
3056 Etyp := Etype (Designator);
3059 E := First_Entity (Designator);
3061 and then Is_Formal (E)
3062 and then not Is_Controlling_Formal (E)
3070 if Is_Access_Type (Etyp) then
3071 Etyp := Directly_Designated_Type (Etyp);
3074 if Is_Interface (Etyp)
3075 and then not Is_Abstract_Subprogram (Designator)
3076 and then not (Ekind (Designator) = E_Procedure
3077 and then Null_Present (Specification (N)))
3079 Error_Msg_Name_1 := Chars (Defining_Entity (N));
3081 ("(Ada 2005) interface subprogram % must be abstract or null",
3087 -- What is the following code for, it used to be
3089 -- ??? Set_Suppress_Elaboration_Checks
3090 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
3092 -- The following seems equivalent, but a bit dubious
3094 if Elaboration_Checks_Suppressed (Designator) then
3095 Set_Kill_Elaboration_Checks (Designator);
3098 if Scop /= Standard_Standard
3099 and then not Is_Child_Unit (Designator)
3101 Set_Categorization_From_Scope (Designator, Scop);
3103 -- For a compilation unit, check for library-unit pragmas
3105 Push_Scope (Designator);
3106 Set_Categorization_From_Pragmas (N);
3107 Validate_Categorization_Dependency (N, Designator);
3111 -- For a compilation unit, set body required. This flag will only be
3112 -- reset if a valid Import or Interface pragma is processed later on.
3114 if Nkind (Parent (N)) = N_Compilation_Unit then
3115 Set_Body_Required (Parent (N), True);
3117 if Ada_Version >= Ada_2005
3118 and then Nkind (Specification (N)) = N_Procedure_Specification
3119 and then Null_Present (Specification (N))
3122 ("null procedure cannot be declared at library level", N);
3126 Generate_Reference_To_Formals (Designator);
3127 Check_Eliminated (Designator);
3129 if Debug_Flag_C then
3131 Write_Str ("<== subprogram spec ");
3132 Write_Name (Chars (Designator));
3133 Write_Str (" from ");
3134 Write_Location (Sloc (N));
3138 if Is_Protected_Type (Current_Scope) then
3140 -- Indicate that this is a protected operation, because it may be
3141 -- used in subsequent declarations within the protected type.
3143 Set_Convention (Designator, Convention_Protected);
3146 List_Inherited_Pre_Post_Aspects (Designator);
3148 if Has_Aspects (N) then
3149 Analyze_Aspect_Specifications (N, Designator);
3151 end Analyze_Subprogram_Declaration;
3153 --------------------------------------
3154 -- Analyze_Subprogram_Specification --
3155 --------------------------------------
3157 -- Reminder: N here really is a subprogram specification (not a subprogram
3158 -- declaration). This procedure is called to analyze the specification in
3159 -- both subprogram bodies and subprogram declarations (specs).
3161 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
3162 Designator : constant Entity_Id := Defining_Entity (N);
3163 Formals : constant List_Id := Parameter_Specifications (N);
3165 -- Start of processing for Analyze_Subprogram_Specification
3168 -- User-defined operator is not allowed in SPARK, except as a renaming
3170 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
3171 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
3173 Check_SPARK_Restriction ("user-defined operator is not allowed", N);
3176 -- Proceed with analysis
3178 Generate_Definition (Designator);
3179 Set_Contract (Designator, Make_Contract (Sloc (Designator)));
3181 if Nkind (N) = N_Function_Specification then
3182 Set_Ekind (Designator, E_Function);
3183 Set_Mechanism (Designator, Default_Mechanism);
3185 Set_Ekind (Designator, E_Procedure);
3186 Set_Etype (Designator, Standard_Void_Type);
3189 -- Introduce new scope for analysis of the formals and the return type
3191 Set_Scope (Designator, Current_Scope);
3193 if Present (Formals) then
3194 Push_Scope (Designator);
3195 Process_Formals (Formals, N);
3197 -- Ada 2005 (AI-345): If this is an overriding operation of an
3198 -- inherited interface operation, and the controlling type is
3199 -- a synchronized type, replace the type with its corresponding
3200 -- record, to match the proper signature of an overriding operation.
3201 -- Same processing for an access parameter whose designated type is
3202 -- derived from a synchronized interface.
3204 if Ada_Version >= Ada_2005 then
3207 Formal_Typ : Entity_Id;
3208 Rec_Typ : Entity_Id;
3209 Desig_Typ : Entity_Id;
3212 Formal := First_Formal (Designator);
3213 while Present (Formal) loop
3214 Formal_Typ := Etype (Formal);
3216 if Is_Concurrent_Type (Formal_Typ)
3217 and then Present (Corresponding_Record_Type (Formal_Typ))
3219 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
3221 if Present (Interfaces (Rec_Typ)) then
3222 Set_Etype (Formal, Rec_Typ);
3225 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
3226 Desig_Typ := Designated_Type (Formal_Typ);
3228 if Is_Concurrent_Type (Desig_Typ)
3229 and then Present (Corresponding_Record_Type (Desig_Typ))
3231 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
3233 if Present (Interfaces (Rec_Typ)) then
3234 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
3239 Next_Formal (Formal);
3246 -- The subprogram scope is pushed and popped around the processing of
3247 -- the return type for consistency with call above to Process_Formals
3248 -- (which itself can call Analyze_Return_Type), and to ensure that any
3249 -- itype created for the return type will be associated with the proper
3252 elsif Nkind (N) = N_Function_Specification then
3253 Push_Scope (Designator);
3254 Analyze_Return_Type (N);
3260 if Nkind (N) = N_Function_Specification then
3262 -- Deal with operator symbol case
3264 if Nkind (Designator) = N_Defining_Operator_Symbol then
3265 Valid_Operator_Definition (Designator);
3268 May_Need_Actuals (Designator);
3270 -- Ada 2005 (AI-251): If the return type is abstract, verify that
3271 -- the subprogram is abstract also. This does not apply to renaming
3272 -- declarations, where abstractness is inherited.
3274 -- In case of primitives associated with abstract interface types
3275 -- the check is applied later (see Analyze_Subprogram_Declaration).
3277 if not Nkind_In (Parent (N), N_Subprogram_Renaming_Declaration,
3278 N_Abstract_Subprogram_Declaration,
3279 N_Formal_Abstract_Subprogram_Declaration)
3281 if Is_Abstract_Type (Etype (Designator))
3282 and then not Is_Interface (Etype (Designator))
3285 ("function that returns abstract type must be abstract", N);
3287 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
3288 -- access result whose designated type is abstract.
3290 elsif Nkind (Result_Definition (N)) = N_Access_Definition
3292 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
3293 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
3294 and then Ada_Version >= Ada_2012
3296 Error_Msg_N ("function whose access result designates "
3297 & "abstract type must be abstract", N);
3303 end Analyze_Subprogram_Specification;
3305 --------------------------
3306 -- Build_Body_To_Inline --
3307 --------------------------
3309 procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id) is
3310 Decl : constant Node_Id := Unit_Declaration_Node (Subp);
3311 Original_Body : Node_Id;
3312 Body_To_Analyze : Node_Id;
3313 Max_Size : constant := 10;
3314 Stat_Count : Integer := 0;
3316 function Has_Excluded_Declaration (Decls : List_Id) return Boolean;
3317 -- Check for declarations that make inlining not worthwhile
3319 function Has_Excluded_Statement (Stats : List_Id) return Boolean;
3320 -- Check for statements that make inlining not worthwhile: any tasking
3321 -- statement, nested at any level. Keep track of total number of
3322 -- elementary statements, as a measure of acceptable size.
3324 function Has_Pending_Instantiation return Boolean;
3325 -- If some enclosing body contains instantiations that appear before the
3326 -- corresponding generic body, the enclosing body has a freeze node so
3327 -- that it can be elaborated after the generic itself. This might
3328 -- conflict with subsequent inlinings, so that it is unsafe to try to
3329 -- inline in such a case.
3331 function Has_Single_Return return Boolean;
3332 -- In general we cannot inline functions that return unconstrained type.
3333 -- However, we can handle such functions if all return statements return
3334 -- a local variable that is the only declaration in the body of the
3335 -- function. In that case the call can be replaced by that local
3336 -- variable as is done for other inlined calls.
3338 procedure Remove_Pragmas;
3339 -- A pragma Unreferenced or pragma Unmodified that mentions a formal
3340 -- parameter has no meaning when the body is inlined and the formals
3341 -- are rewritten. Remove it from body to inline. The analysis of the
3342 -- non-inlined body will handle the pragma properly.
3344 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean;
3345 -- If the body of the subprogram includes a call that returns an
3346 -- unconstrained type, the secondary stack is involved, and it
3347 -- is not worth inlining.
3349 ------------------------------
3350 -- Has_Excluded_Declaration --
3351 ------------------------------
3353 function Has_Excluded_Declaration (Decls : List_Id) return Boolean is
3356 function Is_Unchecked_Conversion (D : Node_Id) return Boolean;
3357 -- Nested subprograms make a given body ineligible for inlining, but
3358 -- we make an exception for instantiations of unchecked conversion.
3359 -- The body has not been analyzed yet, so check the name, and verify
3360 -- that the visible entity with that name is the predefined unit.
3362 -----------------------------
3363 -- Is_Unchecked_Conversion --
3364 -----------------------------
3366 function Is_Unchecked_Conversion (D : Node_Id) return Boolean is
3367 Id : constant Node_Id := Name (D);
3371 if Nkind (Id) = N_Identifier
3372 and then Chars (Id) = Name_Unchecked_Conversion
3374 Conv := Current_Entity (Id);
3376 elsif Nkind_In (Id, N_Selected_Component, N_Expanded_Name)
3377 and then Chars (Selector_Name (Id)) = Name_Unchecked_Conversion
3379 Conv := Current_Entity (Selector_Name (Id));
3384 return Present (Conv)
3385 and then Is_Predefined_File_Name
3386 (Unit_File_Name (Get_Source_Unit (Conv)))
3387 and then Is_Intrinsic_Subprogram (Conv);
3388 end Is_Unchecked_Conversion;
3390 -- Start of processing for Has_Excluded_Declaration
3394 while Present (D) loop
3395 if (Nkind (D) = N_Function_Instantiation
3396 and then not Is_Unchecked_Conversion (D))
3397 or else Nkind_In (D, N_Protected_Type_Declaration,
3398 N_Package_Declaration,
3399 N_Package_Instantiation,
3401 N_Procedure_Instantiation,
3402 N_Task_Type_Declaration)
3405 ("cannot inline & (non-allowed declaration)?", D, Subp);
3413 end Has_Excluded_Declaration;
3415 ----------------------------
3416 -- Has_Excluded_Statement --
3417 ----------------------------
3419 function Has_Excluded_Statement (Stats : List_Id) return Boolean is
3425 while Present (S) loop
3426 Stat_Count := Stat_Count + 1;
3428 if Nkind_In (S, N_Abort_Statement,
3429 N_Asynchronous_Select,
3430 N_Conditional_Entry_Call,
3431 N_Delay_Relative_Statement,
3432 N_Delay_Until_Statement,
3437 ("cannot inline & (non-allowed statement)?", S, Subp);
3440 elsif Nkind (S) = N_Block_Statement then
3441 if Present (Declarations (S))
3442 and then Has_Excluded_Declaration (Declarations (S))
3446 elsif Present (Handled_Statement_Sequence (S))
3449 (Exception_Handlers (Handled_Statement_Sequence (S)))
3451 Has_Excluded_Statement
3452 (Statements (Handled_Statement_Sequence (S))))
3457 elsif Nkind (S) = N_Case_Statement then
3458 E := First (Alternatives (S));
3459 while Present (E) loop
3460 if Has_Excluded_Statement (Statements (E)) then
3467 elsif Nkind (S) = N_If_Statement then
3468 if Has_Excluded_Statement (Then_Statements (S)) then
3472 if Present (Elsif_Parts (S)) then
3473 E := First (Elsif_Parts (S));
3474 while Present (E) loop
3475 if Has_Excluded_Statement (Then_Statements (E)) then
3482 if Present (Else_Statements (S))
3483 and then Has_Excluded_Statement (Else_Statements (S))
3488 elsif Nkind (S) = N_Loop_Statement
3489 and then Has_Excluded_Statement (Statements (S))
3493 elsif Nkind (S) = N_Extended_Return_Statement then
3494 if Has_Excluded_Statement
3495 (Statements (Handled_Statement_Sequence (S)))
3497 (Exception_Handlers (Handled_Statement_Sequence (S)))
3507 end Has_Excluded_Statement;
3509 -------------------------------
3510 -- Has_Pending_Instantiation --
3511 -------------------------------
3513 function Has_Pending_Instantiation return Boolean is
3518 while Present (S) loop
3519 if Is_Compilation_Unit (S)
3520 or else Is_Child_Unit (S)
3524 elsif Ekind (S) = E_Package
3525 and then Has_Forward_Instantiation (S)
3534 end Has_Pending_Instantiation;
3536 ------------------------
3537 -- Has_Single_Return --
3538 ------------------------
3540 function Has_Single_Return return Boolean is
3541 Return_Statement : Node_Id := Empty;
3543 function Check_Return (N : Node_Id) return Traverse_Result;
3549 function Check_Return (N : Node_Id) return Traverse_Result is
3551 if Nkind (N) = N_Simple_Return_Statement then
3552 if Present (Expression (N))
3553 and then Is_Entity_Name (Expression (N))
3555 if No (Return_Statement) then
3556 Return_Statement := N;
3559 elsif Chars (Expression (N)) =
3560 Chars (Expression (Return_Statement))
3568 -- A return statement within an extended return is a noop
3571 elsif No (Expression (N))
3572 and then Nkind (Parent (Parent (N))) =
3573 N_Extended_Return_Statement
3578 -- Expression has wrong form
3583 -- We can only inline a build-in-place function if
3584 -- it has a single extended return.
3586 elsif Nkind (N) = N_Extended_Return_Statement then
3587 if No (Return_Statement) then
3588 Return_Statement := N;
3600 function Check_All_Returns is new Traverse_Func (Check_Return);
3602 -- Start of processing for Has_Single_Return
3605 if Check_All_Returns (N) /= OK then
3608 elsif Nkind (Return_Statement) = N_Extended_Return_Statement then
3612 return Present (Declarations (N))
3613 and then Present (First (Declarations (N)))
3614 and then Chars (Expression (Return_Statement)) =
3615 Chars (Defining_Identifier (First (Declarations (N))));
3617 end Has_Single_Return;
3619 --------------------
3620 -- Remove_Pragmas --
3621 --------------------
3623 procedure Remove_Pragmas is
3628 Decl := First (Declarations (Body_To_Analyze));
3629 while Present (Decl) loop
3632 if Nkind (Decl) = N_Pragma
3633 and then (Pragma_Name (Decl) = Name_Unreferenced
3635 Pragma_Name (Decl) = Name_Unmodified)
3644 --------------------------
3645 -- Uses_Secondary_Stack --
3646 --------------------------
3648 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean is
3649 function Check_Call (N : Node_Id) return Traverse_Result;
3650 -- Look for function calls that return an unconstrained type
3656 function Check_Call (N : Node_Id) return Traverse_Result is
3658 if Nkind (N) = N_Function_Call
3659 and then Is_Entity_Name (Name (N))
3660 and then Is_Composite_Type (Etype (Entity (Name (N))))
3661 and then not Is_Constrained (Etype (Entity (Name (N))))
3664 ("cannot inline & (call returns unconstrained type)?",
3672 function Check_Calls is new Traverse_Func (Check_Call);
3675 return Check_Calls (Bod) = Abandon;
3676 end Uses_Secondary_Stack;
3678 -- Start of processing for Build_Body_To_Inline
3681 -- Return immediately if done already
3683 if Nkind (Decl) = N_Subprogram_Declaration
3684 and then Present (Body_To_Inline (Decl))
3688 -- Functions that return unconstrained composite types require
3689 -- secondary stack handling, and cannot currently be inlined, unless
3690 -- all return statements return a local variable that is the first
3691 -- local declaration in the body.
3693 elsif Ekind (Subp) = E_Function
3694 and then not Is_Scalar_Type (Etype (Subp))
3695 and then not Is_Access_Type (Etype (Subp))
3696 and then not Is_Constrained (Etype (Subp))
3698 if not Has_Single_Return then
3700 ("cannot inline & (unconstrained return type)?", N, Subp);
3704 -- Ditto for functions that return controlled types, where controlled
3705 -- actions interfere in complex ways with inlining.
3707 elsif Ekind (Subp) = E_Function
3708 and then Needs_Finalization (Etype (Subp))
3711 ("cannot inline & (controlled return type)?", N, Subp);
3715 if Present (Declarations (N))
3716 and then Has_Excluded_Declaration (Declarations (N))
3721 if Present (Handled_Statement_Sequence (N)) then
3722 if Present (Exception_Handlers (Handled_Statement_Sequence (N))) then
3724 ("cannot inline& (exception handler)?",
3725 First (Exception_Handlers (Handled_Statement_Sequence (N))),
3729 Has_Excluded_Statement
3730 (Statements (Handled_Statement_Sequence (N)))
3736 -- We do not inline a subprogram that is too large, unless it is
3737 -- marked Inline_Always. This pragma does not suppress the other
3738 -- checks on inlining (forbidden declarations, handlers, etc).
3740 if Stat_Count > Max_Size
3741 and then not Has_Pragma_Inline_Always (Subp)
3743 Cannot_Inline ("cannot inline& (body too large)?", N, Subp);
3747 if Has_Pending_Instantiation then
3749 ("cannot inline& (forward instance within enclosing body)?",
3754 -- Within an instance, the body to inline must be treated as a nested
3755 -- generic, so that the proper global references are preserved.
3757 -- Note that we do not do this at the library level, because it is not
3758 -- needed, and furthermore this causes trouble if front end inlining
3759 -- is activated (-gnatN).
3761 if In_Instance and then Scope (Current_Scope) /= Standard_Standard then
3762 Save_Env (Scope (Current_Scope), Scope (Current_Scope));
3763 Original_Body := Copy_Generic_Node (N, Empty, True);
3765 Original_Body := Copy_Separate_Tree (N);
3768 -- We need to capture references to the formals in order to substitute
3769 -- the actuals at the point of inlining, i.e. instantiation. To treat
3770 -- the formals as globals to the body to inline, we nest it within
3771 -- a dummy parameterless subprogram, declared within the real one.
3772 -- To avoid generating an internal name (which is never public, and
3773 -- which affects serial numbers of other generated names), we use
3774 -- an internal symbol that cannot conflict with user declarations.
3776 Set_Parameter_Specifications (Specification (Original_Body), No_List);
3777 Set_Defining_Unit_Name
3778 (Specification (Original_Body),
3779 Make_Defining_Identifier (Sloc (N), Name_uParent));
3780 Set_Corresponding_Spec (Original_Body, Empty);
3782 Body_To_Analyze := Copy_Generic_Node (Original_Body, Empty, False);
3784 -- Set return type of function, which is also global and does not need
3787 if Ekind (Subp) = E_Function then
3788 Set_Result_Definition (Specification (Body_To_Analyze),
3789 New_Occurrence_Of (Etype (Subp), Sloc (N)));
3792 if No (Declarations (N)) then
3793 Set_Declarations (N, New_List (Body_To_Analyze));
3795 Append (Body_To_Analyze, Declarations (N));
3798 Expander_Mode_Save_And_Set (False);
3801 Analyze (Body_To_Analyze);
3802 Push_Scope (Defining_Entity (Body_To_Analyze));
3803 Save_Global_References (Original_Body);
3805 Remove (Body_To_Analyze);
3807 Expander_Mode_Restore;
3809 -- Restore environment if previously saved
3811 if In_Instance and then Scope (Current_Scope) /= Standard_Standard then
3815 -- If secondary stk used there is no point in inlining. We have
3816 -- already issued the warning in this case, so nothing to do.
3818 if Uses_Secondary_Stack (Body_To_Analyze) then
3822 Set_Body_To_Inline (Decl, Original_Body);
3823 Set_Ekind (Defining_Entity (Original_Body), Ekind (Subp));
3824 Set_Is_Inlined (Subp);
3825 end Build_Body_To_Inline;
3831 procedure Cannot_Inline (Msg : String; N : Node_Id; Subp : Entity_Id) is
3833 -- Do not emit warning if this is a predefined unit which is not the
3834 -- main unit. With validity checks enabled, some predefined subprograms
3835 -- may contain nested subprograms and become ineligible for inlining.
3837 if Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (Subp)))
3838 and then not In_Extended_Main_Source_Unit (Subp)
3842 elsif Has_Pragma_Inline_Always (Subp) then
3844 -- Remove last character (question mark) to make this into an error,
3845 -- because the Inline_Always pragma cannot be obeyed.
3847 Error_Msg_NE (Msg (Msg'First .. Msg'Last - 1), N, Subp);
3849 elsif Ineffective_Inline_Warnings then
3850 Error_Msg_NE (Msg, N, Subp);
3854 -----------------------
3855 -- Check_Conformance --
3856 -----------------------
3858 procedure Check_Conformance
3859 (New_Id : Entity_Id;
3861 Ctype : Conformance_Type;
3863 Conforms : out Boolean;
3864 Err_Loc : Node_Id := Empty;
3865 Get_Inst : Boolean := False;
3866 Skip_Controlling_Formals : Boolean := False)
3868 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
3869 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
3870 -- If Errmsg is True, then processing continues to post an error message
3871 -- for conformance error on given node. Two messages are output. The
3872 -- first message points to the previous declaration with a general "no
3873 -- conformance" message. The second is the detailed reason, supplied as
3874 -- Msg. The parameter N provide information for a possible & insertion
3875 -- in the message, and also provides the location for posting the
3876 -- message in the absence of a specified Err_Loc location.
3878 -----------------------
3879 -- Conformance_Error --
3880 -----------------------
3882 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
3889 if No (Err_Loc) then
3895 Error_Msg_Sloc := Sloc (Old_Id);
3898 when Type_Conformant =>
3899 Error_Msg_N -- CODEFIX
3900 ("not type conformant with declaration#!", Enode);
3902 when Mode_Conformant =>
3903 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3905 ("not mode conformant with operation inherited#!",
3909 ("not mode conformant with declaration#!", Enode);
3912 when Subtype_Conformant =>
3913 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3915 ("not subtype conformant with operation inherited#!",
3919 ("not subtype conformant with declaration#!", Enode);
3922 when Fully_Conformant =>
3923 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3924 Error_Msg_N -- CODEFIX
3925 ("not fully conformant with operation inherited#!",
3928 Error_Msg_N -- CODEFIX
3929 ("not fully conformant with declaration#!", Enode);
3933 Error_Msg_NE (Msg, Enode, N);
3935 end Conformance_Error;
3939 Old_Type : constant Entity_Id := Etype (Old_Id);
3940 New_Type : constant Entity_Id := Etype (New_Id);
3941 Old_Formal : Entity_Id;
3942 New_Formal : Entity_Id;
3943 Access_Types_Match : Boolean;
3944 Old_Formal_Base : Entity_Id;
3945 New_Formal_Base : Entity_Id;
3947 -- Start of processing for Check_Conformance
3952 -- We need a special case for operators, since they don't appear
3955 if Ctype = Type_Conformant then
3956 if Ekind (New_Id) = E_Operator
3957 and then Operator_Matches_Spec (New_Id, Old_Id)
3963 -- If both are functions/operators, check return types conform
3965 if Old_Type /= Standard_Void_Type
3966 and then New_Type /= Standard_Void_Type
3969 -- If we are checking interface conformance we omit controlling
3970 -- arguments and result, because we are only checking the conformance
3971 -- of the remaining parameters.
3973 if Has_Controlling_Result (Old_Id)
3974 and then Has_Controlling_Result (New_Id)
3975 and then Skip_Controlling_Formals
3979 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
3980 Conformance_Error ("\return type does not match!", New_Id);
3984 -- Ada 2005 (AI-231): In case of anonymous access types check the
3985 -- null-exclusion and access-to-constant attributes match.
3987 if Ada_Version >= Ada_2005
3988 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
3990 (Can_Never_Be_Null (Old_Type)
3991 /= Can_Never_Be_Null (New_Type)
3992 or else Is_Access_Constant (Etype (Old_Type))
3993 /= Is_Access_Constant (Etype (New_Type)))
3995 Conformance_Error ("\return type does not match!", New_Id);
3999 -- If either is a function/operator and the other isn't, error
4001 elsif Old_Type /= Standard_Void_Type
4002 or else New_Type /= Standard_Void_Type
4004 Conformance_Error ("\functions can only match functions!", New_Id);
4008 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
4009 -- If this is a renaming as body, refine error message to indicate that
4010 -- the conflict is with the original declaration. If the entity is not
4011 -- frozen, the conventions don't have to match, the one of the renamed
4012 -- entity is inherited.
4014 if Ctype >= Subtype_Conformant then
4015 if Convention (Old_Id) /= Convention (New_Id) then
4017 if not Is_Frozen (New_Id) then
4020 elsif Present (Err_Loc)
4021 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
4022 and then Present (Corresponding_Spec (Err_Loc))
4024 Error_Msg_Name_1 := Chars (New_Id);
4026 Name_Ada + Convention_Id'Pos (Convention (New_Id));
4027 Conformance_Error ("\prior declaration for% has convention %!");
4030 Conformance_Error ("\calling conventions do not match!");
4035 elsif Is_Formal_Subprogram (Old_Id)
4036 or else Is_Formal_Subprogram (New_Id)
4038 Conformance_Error ("\formal subprograms not allowed!");
4043 -- Deal with parameters
4045 -- Note: we use the entity information, rather than going directly
4046 -- to the specification in the tree. This is not only simpler, but
4047 -- absolutely necessary for some cases of conformance tests between
4048 -- operators, where the declaration tree simply does not exist!
4050 Old_Formal := First_Formal (Old_Id);
4051 New_Formal := First_Formal (New_Id);
4052 while Present (Old_Formal) and then Present (New_Formal) loop
4053 if Is_Controlling_Formal (Old_Formal)
4054 and then Is_Controlling_Formal (New_Formal)
4055 and then Skip_Controlling_Formals
4057 -- The controlling formals will have different types when
4058 -- comparing an interface operation with its match, but both
4059 -- or neither must be access parameters.
4061 if Is_Access_Type (Etype (Old_Formal))
4063 Is_Access_Type (Etype (New_Formal))
4065 goto Skip_Controlling_Formal;
4068 ("\access parameter does not match!", New_Formal);
4072 if Ctype = Fully_Conformant then
4074 -- Names must match. Error message is more accurate if we do
4075 -- this before checking that the types of the formals match.
4077 if Chars (Old_Formal) /= Chars (New_Formal) then
4078 Conformance_Error ("\name & does not match!", New_Formal);
4080 -- Set error posted flag on new formal as well to stop
4081 -- junk cascaded messages in some cases.
4083 Set_Error_Posted (New_Formal);
4087 -- Null exclusion must match
4089 if Null_Exclusion_Present (Parent (Old_Formal))
4091 Null_Exclusion_Present (Parent (New_Formal))
4093 -- Only give error if both come from source. This should be
4094 -- investigated some time, since it should not be needed ???
4096 if Comes_From_Source (Old_Formal)
4098 Comes_From_Source (New_Formal)
4101 ("\null exclusion for & does not match", New_Formal);
4103 -- Mark error posted on the new formal to avoid duplicated
4104 -- complaint about types not matching.
4106 Set_Error_Posted (New_Formal);
4111 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
4112 -- case occurs whenever a subprogram is being renamed and one of its
4113 -- parameters imposes a null exclusion. For example:
4115 -- type T is null record;
4116 -- type Acc_T is access T;
4117 -- subtype Acc_T_Sub is Acc_T;
4119 -- procedure P (Obj : not null Acc_T_Sub); -- itype
4120 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
4123 Old_Formal_Base := Etype (Old_Formal);
4124 New_Formal_Base := Etype (New_Formal);
4127 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
4128 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
4131 Access_Types_Match := Ada_Version >= Ada_2005
4133 -- Ensure that this rule is only applied when New_Id is a
4134 -- renaming of Old_Id.
4136 and then Nkind (Parent (Parent (New_Id))) =
4137 N_Subprogram_Renaming_Declaration
4138 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
4139 and then Present (Entity (Name (Parent (Parent (New_Id)))))
4140 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
4142 -- Now handle the allowed access-type case
4144 and then Is_Access_Type (Old_Formal_Base)
4145 and then Is_Access_Type (New_Formal_Base)
4147 -- The type kinds must match. The only exception occurs with
4148 -- multiple generics of the form:
4151 -- type F is private; type A is private;
4152 -- type F_Ptr is access F; type A_Ptr is access A;
4153 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
4154 -- package F_Pack is ... package A_Pack is
4155 -- package F_Inst is
4156 -- new F_Pack (A, A_Ptr, A_P);
4158 -- When checking for conformance between the parameters of A_P
4159 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
4160 -- because the compiler has transformed A_Ptr into a subtype of
4161 -- F_Ptr. We catch this case in the code below.
4163 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
4165 (Is_Generic_Type (Old_Formal_Base)
4166 and then Is_Generic_Type (New_Formal_Base)
4167 and then Is_Internal (New_Formal_Base)
4168 and then Etype (Etype (New_Formal_Base)) =
4170 and then Directly_Designated_Type (Old_Formal_Base) =
4171 Directly_Designated_Type (New_Formal_Base)
4172 and then ((Is_Itype (Old_Formal_Base)
4173 and then Can_Never_Be_Null (Old_Formal_Base))
4175 (Is_Itype (New_Formal_Base)
4176 and then Can_Never_Be_Null (New_Formal_Base)));
4178 -- Types must always match. In the visible part of an instance,
4179 -- usual overloading rules for dispatching operations apply, and
4180 -- we check base types (not the actual subtypes).
4182 if In_Instance_Visible_Part
4183 and then Is_Dispatching_Operation (New_Id)
4185 if not Conforming_Types
4186 (T1 => Base_Type (Etype (Old_Formal)),
4187 T2 => Base_Type (Etype (New_Formal)),
4189 Get_Inst => Get_Inst)
4190 and then not Access_Types_Match
4192 Conformance_Error ("\type of & does not match!", New_Formal);
4196 elsif not Conforming_Types
4197 (T1 => Old_Formal_Base,
4198 T2 => New_Formal_Base,
4200 Get_Inst => Get_Inst)
4201 and then not Access_Types_Match
4203 -- Don't give error message if old type is Any_Type. This test
4204 -- avoids some cascaded errors, e.g. in case of a bad spec.
4206 if Errmsg and then Old_Formal_Base = Any_Type then
4209 Conformance_Error ("\type of & does not match!", New_Formal);
4215 -- For mode conformance, mode must match
4217 if Ctype >= Mode_Conformant then
4218 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
4219 Conformance_Error ("\mode of & does not match!", New_Formal);
4222 -- Part of mode conformance for access types is having the same
4223 -- constant modifier.
4225 elsif Access_Types_Match
4226 and then Is_Access_Constant (Old_Formal_Base) /=
4227 Is_Access_Constant (New_Formal_Base)
4230 ("\constant modifier does not match!", New_Formal);
4235 if Ctype >= Subtype_Conformant then
4237 -- Ada 2005 (AI-231): In case of anonymous access types check
4238 -- the null-exclusion and access-to-constant attributes must
4239 -- match. For null exclusion, we test the types rather than the
4240 -- formals themselves, since the attribute is only set reliably
4241 -- on the formals in the Ada 95 case, and we exclude the case
4242 -- where Old_Formal is marked as controlling, to avoid errors
4243 -- when matching completing bodies with dispatching declarations
4244 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
4246 if Ada_Version >= Ada_2005
4247 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
4248 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
4250 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
4251 Can_Never_Be_Null (Etype (New_Formal))
4253 not Is_Controlling_Formal (Old_Formal))
4255 Is_Access_Constant (Etype (Old_Formal)) /=
4256 Is_Access_Constant (Etype (New_Formal)))
4258 -- Do not complain if error already posted on New_Formal. This
4259 -- avoids some redundant error messages.
4261 and then not Error_Posted (New_Formal)
4263 -- It is allowed to omit the null-exclusion in case of stream
4264 -- attribute subprograms. We recognize stream subprograms
4265 -- through their TSS-generated suffix.
4268 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
4270 if TSS_Name /= TSS_Stream_Read
4271 and then TSS_Name /= TSS_Stream_Write
4272 and then TSS_Name /= TSS_Stream_Input
4273 and then TSS_Name /= TSS_Stream_Output
4276 ("\type of & does not match!", New_Formal);
4283 -- Full conformance checks
4285 if Ctype = Fully_Conformant then
4287 -- We have checked already that names match
4289 if Parameter_Mode (Old_Formal) = E_In_Parameter then
4291 -- Check default expressions for in parameters
4294 NewD : constant Boolean :=
4295 Present (Default_Value (New_Formal));
4296 OldD : constant Boolean :=
4297 Present (Default_Value (Old_Formal));
4299 if NewD or OldD then
4301 -- The old default value has been analyzed because the
4302 -- current full declaration will have frozen everything
4303 -- before. The new default value has not been analyzed,
4304 -- so analyze it now before we check for conformance.
4307 Push_Scope (New_Id);
4308 Preanalyze_Spec_Expression
4309 (Default_Value (New_Formal), Etype (New_Formal));
4313 if not (NewD and OldD)
4314 or else not Fully_Conformant_Expressions
4315 (Default_Value (Old_Formal),
4316 Default_Value (New_Formal))
4319 ("\default expression for & does not match!",
4328 -- A couple of special checks for Ada 83 mode. These checks are
4329 -- skipped if either entity is an operator in package Standard,
4330 -- or if either old or new instance is not from the source program.
4332 if Ada_Version = Ada_83
4333 and then Sloc (Old_Id) > Standard_Location
4334 and then Sloc (New_Id) > Standard_Location
4335 and then Comes_From_Source (Old_Id)
4336 and then Comes_From_Source (New_Id)
4339 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
4340 New_Param : constant Node_Id := Declaration_Node (New_Formal);
4343 -- Explicit IN must be present or absent in both cases. This
4344 -- test is required only in the full conformance case.
4346 if In_Present (Old_Param) /= In_Present (New_Param)
4347 and then Ctype = Fully_Conformant
4350 ("\(Ada 83) IN must appear in both declarations",
4355 -- Grouping (use of comma in param lists) must be the same
4356 -- This is where we catch a misconformance like:
4359 -- A : Integer; B : Integer
4361 -- which are represented identically in the tree except
4362 -- for the setting of the flags More_Ids and Prev_Ids.
4364 if More_Ids (Old_Param) /= More_Ids (New_Param)
4365 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
4368 ("\grouping of & does not match!", New_Formal);
4374 -- This label is required when skipping controlling formals
4376 <<Skip_Controlling_Formal>>
4378 Next_Formal (Old_Formal);
4379 Next_Formal (New_Formal);
4382 if Present (Old_Formal) then
4383 Conformance_Error ("\too few parameters!");
4386 elsif Present (New_Formal) then
4387 Conformance_Error ("\too many parameters!", New_Formal);
4390 end Check_Conformance;
4392 -----------------------
4393 -- Check_Conventions --
4394 -----------------------
4396 procedure Check_Conventions (Typ : Entity_Id) is
4397 Ifaces_List : Elist_Id;
4399 procedure Check_Convention (Op : Entity_Id);
4400 -- Verify that the convention of inherited dispatching operation Op is
4401 -- consistent among all subprograms it overrides. In order to minimize
4402 -- the search, Search_From is utilized to designate a specific point in
4403 -- the list rather than iterating over the whole list once more.
4405 ----------------------
4406 -- Check_Convention --
4407 ----------------------
4409 procedure Check_Convention (Op : Entity_Id) is
4410 Iface_Elmt : Elmt_Id;
4411 Iface_Prim_Elmt : Elmt_Id;
4412 Iface_Prim : Entity_Id;
4415 Iface_Elmt := First_Elmt (Ifaces_List);
4416 while Present (Iface_Elmt) loop
4418 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
4419 while Present (Iface_Prim_Elmt) loop
4420 Iface_Prim := Node (Iface_Prim_Elmt);
4422 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
4423 and then Convention (Iface_Prim) /= Convention (Op)
4426 ("inconsistent conventions in primitive operations", Typ);
4428 Error_Msg_Name_1 := Chars (Op);
4429 Error_Msg_Name_2 := Get_Convention_Name (Convention (Op));
4430 Error_Msg_Sloc := Sloc (Op);
4432 if Comes_From_Source (Op) or else No (Alias (Op)) then
4433 if not Present (Overridden_Operation (Op)) then
4434 Error_Msg_N ("\\primitive % defined #", Typ);
4437 ("\\overriding operation % with " &
4438 "convention % defined #", Typ);
4441 else pragma Assert (Present (Alias (Op)));
4442 Error_Msg_Sloc := Sloc (Alias (Op));
4444 ("\\inherited operation % with " &
4445 "convention % defined #", Typ);
4448 Error_Msg_Name_1 := Chars (Op);
4450 Get_Convention_Name (Convention (Iface_Prim));
4451 Error_Msg_Sloc := Sloc (Iface_Prim);
4453 ("\\overridden operation % with " &
4454 "convention % defined #", Typ);
4456 -- Avoid cascading errors
4461 Next_Elmt (Iface_Prim_Elmt);
4464 Next_Elmt (Iface_Elmt);
4466 end Check_Convention;
4470 Prim_Op : Entity_Id;
4471 Prim_Op_Elmt : Elmt_Id;
4473 -- Start of processing for Check_Conventions
4476 if not Has_Interfaces (Typ) then
4480 Collect_Interfaces (Typ, Ifaces_List);
4482 -- The algorithm checks every overriding dispatching operation against
4483 -- all the corresponding overridden dispatching operations, detecting
4484 -- differences in conventions.
4486 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
4487 while Present (Prim_Op_Elmt) loop
4488 Prim_Op := Node (Prim_Op_Elmt);
4490 -- A small optimization: skip the predefined dispatching operations
4491 -- since they always have the same convention.
4493 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
4494 Check_Convention (Prim_Op);
4497 Next_Elmt (Prim_Op_Elmt);
4499 end Check_Conventions;
4501 ------------------------------
4502 -- Check_Delayed_Subprogram --
4503 ------------------------------
4505 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
4508 procedure Possible_Freeze (T : Entity_Id);
4509 -- T is the type of either a formal parameter or of the return type.
4510 -- If T is not yet frozen and needs a delayed freeze, then the
4511 -- subprogram itself must be delayed. If T is the limited view of an
4512 -- incomplete type the subprogram must be frozen as well, because
4513 -- T may depend on local types that have not been frozen yet.
4515 ---------------------
4516 -- Possible_Freeze --
4517 ---------------------
4519 procedure Possible_Freeze (T : Entity_Id) is
4521 if Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
4522 Set_Has_Delayed_Freeze (Designator);
4524 elsif Is_Access_Type (T)
4525 and then Has_Delayed_Freeze (Designated_Type (T))
4526 and then not Is_Frozen (Designated_Type (T))
4528 Set_Has_Delayed_Freeze (Designator);
4530 elsif Ekind (T) = E_Incomplete_Type and then From_With_Type (T) then
4531 Set_Has_Delayed_Freeze (Designator);
4533 -- AI05-0151: In Ada 2012, Incomplete types can appear in the profile
4534 -- of a subprogram or entry declaration.
4536 elsif Ekind (T) = E_Incomplete_Type
4537 and then Ada_Version >= Ada_2012
4539 Set_Has_Delayed_Freeze (Designator);
4542 end Possible_Freeze;
4544 -- Start of processing for Check_Delayed_Subprogram
4547 -- All subprograms, including abstract subprograms, may need a freeze
4548 -- node if some formal type or the return type needs one.
4550 Possible_Freeze (Etype (Designator));
4551 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
4553 -- Need delayed freeze if any of the formal types themselves need
4554 -- a delayed freeze and are not yet frozen.
4556 F := First_Formal (Designator);
4557 while Present (F) loop
4558 Possible_Freeze (Etype (F));
4559 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
4563 -- Mark functions that return by reference. Note that it cannot be
4564 -- done for delayed_freeze subprograms because the underlying
4565 -- returned type may not be known yet (for private types)
4567 if not Has_Delayed_Freeze (Designator)
4568 and then Expander_Active
4571 Typ : constant Entity_Id := Etype (Designator);
4572 Utyp : constant Entity_Id := Underlying_Type (Typ);
4575 if Is_Immutably_Limited_Type (Typ) then
4576 Set_Returns_By_Ref (Designator);
4578 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
4579 Set_Returns_By_Ref (Designator);
4583 end Check_Delayed_Subprogram;
4585 ------------------------------------
4586 -- Check_Discriminant_Conformance --
4587 ------------------------------------
4589 procedure Check_Discriminant_Conformance
4594 Old_Discr : Entity_Id := First_Discriminant (Prev);
4595 New_Discr : Node_Id := First (Discriminant_Specifications (N));
4596 New_Discr_Id : Entity_Id;
4597 New_Discr_Type : Entity_Id;
4599 procedure Conformance_Error (Msg : String; N : Node_Id);
4600 -- Post error message for conformance error on given node. Two messages
4601 -- are output. The first points to the previous declaration with a
4602 -- general "no conformance" message. The second is the detailed reason,
4603 -- supplied as Msg. The parameter N provide information for a possible
4604 -- & insertion in the message.
4606 -----------------------
4607 -- Conformance_Error --
4608 -----------------------
4610 procedure Conformance_Error (Msg : String; N : Node_Id) is
4612 Error_Msg_Sloc := Sloc (Prev_Loc);
4613 Error_Msg_N -- CODEFIX
4614 ("not fully conformant with declaration#!", N);
4615 Error_Msg_NE (Msg, N, N);
4616 end Conformance_Error;
4618 -- Start of processing for Check_Discriminant_Conformance
4621 while Present (Old_Discr) and then Present (New_Discr) loop
4623 New_Discr_Id := Defining_Identifier (New_Discr);
4625 -- The subtype mark of the discriminant on the full type has not
4626 -- been analyzed so we do it here. For an access discriminant a new
4629 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
4631 Access_Definition (N, Discriminant_Type (New_Discr));
4634 Analyze (Discriminant_Type (New_Discr));
4635 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
4637 -- Ada 2005: if the discriminant definition carries a null
4638 -- exclusion, create an itype to check properly for consistency
4639 -- with partial declaration.
4641 if Is_Access_Type (New_Discr_Type)
4642 and then Null_Exclusion_Present (New_Discr)
4645 Create_Null_Excluding_Itype
4646 (T => New_Discr_Type,
4647 Related_Nod => New_Discr,
4648 Scope_Id => Current_Scope);
4652 if not Conforming_Types
4653 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
4655 Conformance_Error ("type of & does not match!", New_Discr_Id);
4658 -- Treat the new discriminant as an occurrence of the old one,
4659 -- for navigation purposes, and fill in some semantic
4660 -- information, for completeness.
4662 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
4663 Set_Etype (New_Discr_Id, Etype (Old_Discr));
4664 Set_Scope (New_Discr_Id, Scope (Old_Discr));
4669 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
4670 Conformance_Error ("name & does not match!", New_Discr_Id);
4674 -- Default expressions must match
4677 NewD : constant Boolean :=
4678 Present (Expression (New_Discr));
4679 OldD : constant Boolean :=
4680 Present (Expression (Parent (Old_Discr)));
4683 if NewD or OldD then
4685 -- The old default value has been analyzed and expanded,
4686 -- because the current full declaration will have frozen
4687 -- everything before. The new default values have not been
4688 -- expanded, so expand now to check conformance.
4691 Preanalyze_Spec_Expression
4692 (Expression (New_Discr), New_Discr_Type);
4695 if not (NewD and OldD)
4696 or else not Fully_Conformant_Expressions
4697 (Expression (Parent (Old_Discr)),
4698 Expression (New_Discr))
4702 ("default expression for & does not match!",
4709 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
4711 if Ada_Version = Ada_83 then
4713 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
4716 -- Grouping (use of comma in param lists) must be the same
4717 -- This is where we catch a misconformance like:
4720 -- A : Integer; B : Integer
4722 -- which are represented identically in the tree except
4723 -- for the setting of the flags More_Ids and Prev_Ids.
4725 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
4726 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
4729 ("grouping of & does not match!", New_Discr_Id);
4735 Next_Discriminant (Old_Discr);
4739 if Present (Old_Discr) then
4740 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
4743 elsif Present (New_Discr) then
4745 ("too many discriminants!", Defining_Identifier (New_Discr));
4748 end Check_Discriminant_Conformance;
4750 ----------------------------
4751 -- Check_Fully_Conformant --
4752 ----------------------------
4754 procedure Check_Fully_Conformant
4755 (New_Id : Entity_Id;
4757 Err_Loc : Node_Id := Empty)
4760 pragma Warnings (Off, Result);
4763 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
4764 end Check_Fully_Conformant;
4766 ---------------------------
4767 -- Check_Mode_Conformant --
4768 ---------------------------
4770 procedure Check_Mode_Conformant
4771 (New_Id : Entity_Id;
4773 Err_Loc : Node_Id := Empty;
4774 Get_Inst : Boolean := False)
4777 pragma Warnings (Off, Result);
4780 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
4781 end Check_Mode_Conformant;
4783 --------------------------------
4784 -- Check_Overriding_Indicator --
4785 --------------------------------
4787 procedure Check_Overriding_Indicator
4789 Overridden_Subp : Entity_Id;
4790 Is_Primitive : Boolean)
4796 -- No overriding indicator for literals
4798 if Ekind (Subp) = E_Enumeration_Literal then
4801 elsif Ekind (Subp) = E_Entry then
4802 Decl := Parent (Subp);
4804 -- No point in analyzing a malformed operator
4806 elsif Nkind (Subp) = N_Defining_Operator_Symbol
4807 and then Error_Posted (Subp)
4812 Decl := Unit_Declaration_Node (Subp);
4815 if Nkind_In (Decl, N_Subprogram_Body,
4816 N_Subprogram_Body_Stub,
4817 N_Subprogram_Declaration,
4818 N_Abstract_Subprogram_Declaration,
4819 N_Subprogram_Renaming_Declaration)
4821 Spec := Specification (Decl);
4823 elsif Nkind (Decl) = N_Entry_Declaration then
4830 -- The overriding operation is type conformant with the overridden one,
4831 -- but the names of the formals are not required to match. If the names
4832 -- appear permuted in the overriding operation, this is a possible
4833 -- source of confusion that is worth diagnosing. Controlling formals
4834 -- often carry names that reflect the type, and it is not worthwhile
4835 -- requiring that their names match.
4837 if Present (Overridden_Subp)
4838 and then Nkind (Subp) /= N_Defining_Operator_Symbol
4845 Form1 := First_Formal (Subp);
4846 Form2 := First_Formal (Overridden_Subp);
4848 -- If the overriding operation is a synchronized operation, skip
4849 -- the first parameter of the overridden operation, which is
4850 -- implicit in the new one. If the operation is declared in the
4851 -- body it is not primitive and all formals must match.
4853 if Is_Concurrent_Type (Scope (Subp))
4854 and then Is_Tagged_Type (Scope (Subp))
4855 and then not Has_Completion (Scope (Subp))
4857 Form2 := Next_Formal (Form2);
4860 if Present (Form1) then
4861 Form1 := Next_Formal (Form1);
4862 Form2 := Next_Formal (Form2);
4865 while Present (Form1) loop
4866 if not Is_Controlling_Formal (Form1)
4867 and then Present (Next_Formal (Form2))
4868 and then Chars (Form1) = Chars (Next_Formal (Form2))
4870 Error_Msg_Node_2 := Alias (Overridden_Subp);
4871 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
4873 ("& does not match corresponding formal of&#",
4878 Next_Formal (Form1);
4879 Next_Formal (Form2);
4884 -- If there is an overridden subprogram, then check that there is no
4885 -- "not overriding" indicator, and mark the subprogram as overriding.
4886 -- This is not done if the overridden subprogram is marked as hidden,
4887 -- which can occur for the case of inherited controlled operations
4888 -- (see Derive_Subprogram), unless the inherited subprogram's parent
4889 -- subprogram is not itself hidden. (Note: This condition could probably
4890 -- be simplified, leaving out the testing for the specific controlled
4891 -- cases, but it seems safer and clearer this way, and echoes similar
4892 -- special-case tests of this kind in other places.)
4894 if Present (Overridden_Subp)
4895 and then (not Is_Hidden (Overridden_Subp)
4897 ((Chars (Overridden_Subp) = Name_Initialize
4899 Chars (Overridden_Subp) = Name_Adjust
4901 Chars (Overridden_Subp) = Name_Finalize)
4902 and then Present (Alias (Overridden_Subp))
4903 and then not Is_Hidden (Alias (Overridden_Subp))))
4905 if Must_Not_Override (Spec) then
4906 Error_Msg_Sloc := Sloc (Overridden_Subp);
4908 if Ekind (Subp) = E_Entry then
4910 ("entry & overrides inherited operation #", Spec, Subp);
4913 ("subprogram & overrides inherited operation #", Spec, Subp);
4916 elsif Is_Subprogram (Subp) then
4917 if Is_Init_Proc (Subp) then
4920 elsif No (Overridden_Operation (Subp)) then
4922 -- For entities generated by Derive_Subprograms the overridden
4923 -- operation is the inherited primitive (which is available
4924 -- through the attribute alias)
4926 if (Is_Dispatching_Operation (Subp)
4927 or else Is_Dispatching_Operation (Overridden_Subp))
4928 and then not Comes_From_Source (Overridden_Subp)
4929 and then Find_Dispatching_Type (Overridden_Subp) =
4930 Find_Dispatching_Type (Subp)
4931 and then Present (Alias (Overridden_Subp))
4932 and then Comes_From_Source (Alias (Overridden_Subp))
4934 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
4937 Set_Overridden_Operation (Subp, Overridden_Subp);
4942 -- If primitive flag is set or this is a protected operation, then
4943 -- the operation is overriding at the point of its declaration, so
4944 -- warn if necessary. Otherwise it may have been declared before the
4945 -- operation it overrides and no check is required.
4948 and then not Must_Override (Spec)
4949 and then (Is_Primitive
4950 or else Ekind (Scope (Subp)) = E_Protected_Type)
4952 Style.Missing_Overriding (Decl, Subp);
4955 -- If Subp is an operator, it may override a predefined operation, if
4956 -- it is defined in the same scope as the type to which it applies.
4957 -- In that case Overridden_Subp is empty because of our implicit
4958 -- representation for predefined operators. We have to check whether the
4959 -- signature of Subp matches that of a predefined operator. Note that
4960 -- first argument provides the name of the operator, and the second
4961 -- argument the signature that may match that of a standard operation.
4962 -- If the indicator is overriding, then the operator must match a
4963 -- predefined signature, because we know already that there is no
4964 -- explicit overridden operation.
4966 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
4967 if Must_Not_Override (Spec) then
4969 -- If this is not a primitive or a protected subprogram, then
4970 -- "not overriding" is illegal.
4973 and then Ekind (Scope (Subp)) /= E_Protected_Type
4976 ("overriding indicator only allowed "
4977 & "if subprogram is primitive", Subp);
4979 elsif Can_Override_Operator (Subp) then
4981 ("subprogram& overrides predefined operator ", Spec, Subp);
4984 elsif Must_Override (Spec) then
4985 if No (Overridden_Operation (Subp))
4986 and then not Can_Override_Operator (Subp)
4988 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
4991 elsif not Error_Posted (Subp)
4992 and then Style_Check
4993 and then Can_Override_Operator (Subp)
4995 not Is_Predefined_File_Name
4996 (Unit_File_Name (Get_Source_Unit (Subp)))
4998 -- If style checks are enabled, indicate that the indicator is
4999 -- missing. However, at the point of declaration, the type of
5000 -- which this is a primitive operation may be private, in which
5001 -- case the indicator would be premature.
5003 if Has_Private_Declaration (Etype (Subp))
5004 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
5008 Style.Missing_Overriding (Decl, Subp);
5012 elsif Must_Override (Spec) then
5013 if Ekind (Subp) = E_Entry then
5014 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
5016 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
5019 -- If the operation is marked "not overriding" and it's not primitive
5020 -- then an error is issued, unless this is an operation of a task or
5021 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
5022 -- has been specified have already been checked above.
5024 elsif Must_Not_Override (Spec)
5025 and then not Is_Primitive
5026 and then Ekind (Subp) /= E_Entry
5027 and then Ekind (Scope (Subp)) /= E_Protected_Type
5030 ("overriding indicator only allowed if subprogram is primitive",
5034 end Check_Overriding_Indicator;
5040 -- Note: this procedure needs to know far too much about how the expander
5041 -- messes with exceptions. The use of the flag Exception_Junk and the
5042 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
5043 -- works, but is not very clean. It would be better if the expansion
5044 -- routines would leave Original_Node working nicely, and we could use
5045 -- Original_Node here to ignore all the peculiar expander messing ???
5047 procedure Check_Returns
5051 Proc : Entity_Id := Empty)
5055 procedure Check_Statement_Sequence (L : List_Id);
5056 -- Internal recursive procedure to check a list of statements for proper
5057 -- termination by a return statement (or a transfer of control or a
5058 -- compound statement that is itself internally properly terminated).
5060 ------------------------------
5061 -- Check_Statement_Sequence --
5062 ------------------------------
5064 procedure Check_Statement_Sequence (L : List_Id) is
5069 Raise_Exception_Call : Boolean;
5070 -- Set True if statement sequence terminated by Raise_Exception call
5071 -- or a Reraise_Occurrence call.
5074 Raise_Exception_Call := False;
5076 -- Get last real statement
5078 Last_Stm := Last (L);
5080 -- Deal with digging out exception handler statement sequences that
5081 -- have been transformed by the local raise to goto optimization.
5082 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
5083 -- optimization has occurred, we are looking at something like:
5086 -- original stmts in block
5090 -- goto L1; | omitted if No_Exception_Propagation
5095 -- goto L3; -- skip handler when exception not raised
5097 -- <<L1>> -- target label for local exception
5111 -- and what we have to do is to dig out the estmts1 and estmts2
5112 -- sequences (which were the original sequences of statements in
5113 -- the exception handlers) and check them.
5115 if Nkind (Last_Stm) = N_Label
5116 and then Exception_Junk (Last_Stm)
5122 exit when Nkind (Stm) /= N_Block_Statement;
5123 exit when not Exception_Junk (Stm);
5126 exit when Nkind (Stm) /= N_Label;
5127 exit when not Exception_Junk (Stm);
5128 Check_Statement_Sequence
5129 (Statements (Handled_Statement_Sequence (Next (Stm))));
5134 exit when Nkind (Stm) /= N_Goto_Statement;
5135 exit when not Exception_Junk (Stm);
5139 -- Don't count pragmas
5141 while Nkind (Last_Stm) = N_Pragma
5143 -- Don't count call to SS_Release (can happen after Raise_Exception)
5146 (Nkind (Last_Stm) = N_Procedure_Call_Statement
5148 Nkind (Name (Last_Stm)) = N_Identifier
5150 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
5152 -- Don't count exception junk
5155 (Nkind_In (Last_Stm, N_Goto_Statement,
5157 N_Object_Declaration)
5158 and then Exception_Junk (Last_Stm))
5159 or else Nkind (Last_Stm) in N_Push_xxx_Label
5160 or else Nkind (Last_Stm) in N_Pop_xxx_Label
5165 -- Here we have the "real" last statement
5167 Kind := Nkind (Last_Stm);
5169 -- Transfer of control, OK. Note that in the No_Return procedure
5170 -- case, we already diagnosed any explicit return statements, so
5171 -- we can treat them as OK in this context.
5173 if Is_Transfer (Last_Stm) then
5176 -- Check cases of explicit non-indirect procedure calls
5178 elsif Kind = N_Procedure_Call_Statement
5179 and then Is_Entity_Name (Name (Last_Stm))
5181 -- Check call to Raise_Exception procedure which is treated
5182 -- specially, as is a call to Reraise_Occurrence.
5184 -- We suppress the warning in these cases since it is likely that
5185 -- the programmer really does not expect to deal with the case
5186 -- of Null_Occurrence, and thus would find a warning about a
5187 -- missing return curious, and raising Program_Error does not
5188 -- seem such a bad behavior if this does occur.
5190 -- Note that in the Ada 2005 case for Raise_Exception, the actual
5191 -- behavior will be to raise Constraint_Error (see AI-329).
5193 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
5195 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
5197 Raise_Exception_Call := True;
5199 -- For Raise_Exception call, test first argument, if it is
5200 -- an attribute reference for a 'Identity call, then we know
5201 -- that the call cannot possibly return.
5204 Arg : constant Node_Id :=
5205 Original_Node (First_Actual (Last_Stm));
5207 if Nkind (Arg) = N_Attribute_Reference
5208 and then Attribute_Name (Arg) = Name_Identity
5215 -- If statement, need to look inside if there is an else and check
5216 -- each constituent statement sequence for proper termination.
5218 elsif Kind = N_If_Statement
5219 and then Present (Else_Statements (Last_Stm))
5221 Check_Statement_Sequence (Then_Statements (Last_Stm));
5222 Check_Statement_Sequence (Else_Statements (Last_Stm));
5224 if Present (Elsif_Parts (Last_Stm)) then
5226 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
5229 while Present (Elsif_Part) loop
5230 Check_Statement_Sequence (Then_Statements (Elsif_Part));
5238 -- Case statement, check each case for proper termination
5240 elsif Kind = N_Case_Statement then
5244 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
5245 while Present (Case_Alt) loop
5246 Check_Statement_Sequence (Statements (Case_Alt));
5247 Next_Non_Pragma (Case_Alt);
5253 -- Block statement, check its handled sequence of statements
5255 elsif Kind = N_Block_Statement then
5261 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
5270 -- Loop statement. If there is an iteration scheme, we can definitely
5271 -- fall out of the loop. Similarly if there is an exit statement, we
5272 -- can fall out. In either case we need a following return.
5274 elsif Kind = N_Loop_Statement then
5275 if Present (Iteration_Scheme (Last_Stm))
5276 or else Has_Exit (Entity (Identifier (Last_Stm)))
5280 -- A loop with no exit statement or iteration scheme is either
5281 -- an infinite loop, or it has some other exit (raise/return).
5282 -- In either case, no warning is required.
5288 -- Timed entry call, check entry call and delay alternatives
5290 -- Note: in expanded code, the timed entry call has been converted
5291 -- to a set of expanded statements on which the check will work
5292 -- correctly in any case.
5294 elsif Kind = N_Timed_Entry_Call then
5296 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
5297 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
5300 -- If statement sequence of entry call alternative is missing,
5301 -- then we can definitely fall through, and we post the error
5302 -- message on the entry call alternative itself.
5304 if No (Statements (ECA)) then
5307 -- If statement sequence of delay alternative is missing, then
5308 -- we can definitely fall through, and we post the error
5309 -- message on the delay alternative itself.
5311 -- Note: if both ECA and DCA are missing the return, then we
5312 -- post only one message, should be enough to fix the bugs.
5313 -- If not we will get a message next time on the DCA when the
5316 elsif No (Statements (DCA)) then
5319 -- Else check both statement sequences
5322 Check_Statement_Sequence (Statements (ECA));
5323 Check_Statement_Sequence (Statements (DCA));
5328 -- Conditional entry call, check entry call and else part
5330 -- Note: in expanded code, the conditional entry call has been
5331 -- converted to a set of expanded statements on which the check
5332 -- will work correctly in any case.
5334 elsif Kind = N_Conditional_Entry_Call then
5336 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
5339 -- If statement sequence of entry call alternative is missing,
5340 -- then we can definitely fall through, and we post the error
5341 -- message on the entry call alternative itself.
5343 if No (Statements (ECA)) then
5346 -- Else check statement sequence and else part
5349 Check_Statement_Sequence (Statements (ECA));
5350 Check_Statement_Sequence (Else_Statements (Last_Stm));
5356 -- If we fall through, issue appropriate message
5359 if not Raise_Exception_Call then
5361 ("?RETURN statement missing following this statement!",
5364 ("\?Program_Error may be raised at run time!",
5368 -- Note: we set Err even though we have not issued a warning
5369 -- because we still have a case of a missing return. This is
5370 -- an extremely marginal case, probably will never be noticed
5371 -- but we might as well get it right.
5375 -- Otherwise we have the case of a procedure marked No_Return
5378 if not Raise_Exception_Call then
5380 ("?implied return after this statement " &
5381 "will raise Program_Error",
5384 ("\?procedure & is marked as No_Return!",
5389 RE : constant Node_Id :=
5390 Make_Raise_Program_Error (Sloc (Last_Stm),
5391 Reason => PE_Implicit_Return);
5393 Insert_After (Last_Stm, RE);
5397 end Check_Statement_Sequence;
5399 -- Start of processing for Check_Returns
5403 Check_Statement_Sequence (Statements (HSS));
5405 if Present (Exception_Handlers (HSS)) then
5406 Handler := First_Non_Pragma (Exception_Handlers (HSS));
5407 while Present (Handler) loop
5408 Check_Statement_Sequence (Statements (Handler));
5409 Next_Non_Pragma (Handler);
5414 ----------------------------
5415 -- Check_Subprogram_Order --
5416 ----------------------------
5418 procedure Check_Subprogram_Order (N : Node_Id) is
5420 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
5421 -- This is used to check if S1 > S2 in the sense required by this
5422 -- test, for example nameab < namec, but name2 < name10.
5424 -----------------------------
5425 -- Subprogram_Name_Greater --
5426 -----------------------------
5428 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
5433 -- Remove trailing numeric parts
5436 while S1 (L1) in '0' .. '9' loop
5441 while S2 (L2) in '0' .. '9' loop
5445 -- If non-numeric parts non-equal, that's decisive
5447 if S1 (S1'First .. L1) < S2 (S2'First .. L2) then
5450 elsif S1 (S1'First .. L1) > S2 (S2'First .. L2) then
5453 -- If non-numeric parts equal, compare suffixed numeric parts. Note
5454 -- that a missing suffix is treated as numeric zero in this test.
5458 while L1 < S1'Last loop
5460 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
5464 while L2 < S2'Last loop
5466 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
5471 end Subprogram_Name_Greater;
5473 -- Start of processing for Check_Subprogram_Order
5476 -- Check body in alpha order if this is option
5479 and then Style_Check_Order_Subprograms
5480 and then Nkind (N) = N_Subprogram_Body
5481 and then Comes_From_Source (N)
5482 and then In_Extended_Main_Source_Unit (N)
5486 renames Scope_Stack.Table
5487 (Scope_Stack.Last).Last_Subprogram_Name;
5489 Body_Id : constant Entity_Id :=
5490 Defining_Entity (Specification (N));
5493 Get_Decoded_Name_String (Chars (Body_Id));
5496 if Subprogram_Name_Greater
5497 (LSN.all, Name_Buffer (1 .. Name_Len))
5499 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
5505 LSN := new String'(Name_Buffer (1 .. Name_Len));
5508 end Check_Subprogram_Order;
5510 ------------------------------
5511 -- Check_Subtype_Conformant --
5512 ------------------------------
5514 procedure Check_Subtype_Conformant
5515 (New_Id : Entity_Id;
5517 Err_Loc : Node_Id := Empty;
5518 Skip_Controlling_Formals : Boolean := False)
5521 pragma Warnings (Off, Result);
5524 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
5525 Skip_Controlling_Formals => Skip_Controlling_Formals);
5526 end Check_Subtype_Conformant;
5528 ---------------------------
5529 -- Check_Type_Conformant --
5530 ---------------------------
5532 procedure Check_Type_Conformant
5533 (New_Id : Entity_Id;
5535 Err_Loc : Node_Id := Empty)
5538 pragma Warnings (Off, Result);
5541 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
5542 end Check_Type_Conformant;
5544 ---------------------------
5545 -- Can_Override_Operator --
5546 ---------------------------
5548 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
5551 if Nkind (Subp) /= N_Defining_Operator_Symbol then
5555 Typ := Base_Type (Etype (First_Formal (Subp)));
5557 return Operator_Matches_Spec (Subp, Subp)
5558 and then Scope (Subp) = Scope (Typ)
5559 and then not Is_Class_Wide_Type (Typ);
5561 end Can_Override_Operator;
5563 ----------------------
5564 -- Conforming_Types --
5565 ----------------------
5567 function Conforming_Types
5570 Ctype : Conformance_Type;
5571 Get_Inst : Boolean := False) return Boolean
5573 Type_1 : Entity_Id := T1;
5574 Type_2 : Entity_Id := T2;
5575 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
5577 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean;
5578 -- If neither T1 nor T2 are generic actual types, or if they are in
5579 -- different scopes (e.g. parent and child instances), then verify that
5580 -- the base types are equal. Otherwise T1 and T2 must be on the same
5581 -- subtype chain. The whole purpose of this procedure is to prevent
5582 -- spurious ambiguities in an instantiation that may arise if two
5583 -- distinct generic types are instantiated with the same actual.
5585 function Find_Designated_Type (T : Entity_Id) return Entity_Id;
5586 -- An access parameter can designate an incomplete type. If the
5587 -- incomplete type is the limited view of a type from a limited_
5588 -- with_clause, check whether the non-limited view is available. If
5589 -- it is a (non-limited) incomplete type, get the full view.
5591 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean;
5592 -- Returns True if and only if either T1 denotes a limited view of T2
5593 -- or T2 denotes a limited view of T1. This can arise when the limited
5594 -- with view of a type is used in a subprogram declaration and the
5595 -- subprogram body is in the scope of a regular with clause for the
5596 -- same unit. In such a case, the two type entities can be considered
5597 -- identical for purposes of conformance checking.
5599 ----------------------
5600 -- Base_Types_Match --
5601 ----------------------
5603 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean is
5608 elsif Base_Type (T1) = Base_Type (T2) then
5610 -- The following is too permissive. A more precise test should
5611 -- check that the generic actual is an ancestor subtype of the
5614 return not Is_Generic_Actual_Type (T1)
5615 or else not Is_Generic_Actual_Type (T2)
5616 or else Scope (T1) /= Scope (T2);
5621 end Base_Types_Match;
5623 --------------------------
5624 -- Find_Designated_Type --
5625 --------------------------
5627 function Find_Designated_Type (T : Entity_Id) return Entity_Id is
5631 Desig := Directly_Designated_Type (T);
5633 if Ekind (Desig) = E_Incomplete_Type then
5635 -- If regular incomplete type, get full view if available
5637 if Present (Full_View (Desig)) then
5638 Desig := Full_View (Desig);
5640 -- If limited view of a type, get non-limited view if available,
5641 -- and check again for a regular incomplete type.
5643 elsif Present (Non_Limited_View (Desig)) then
5644 Desig := Get_Full_View (Non_Limited_View (Desig));
5649 end Find_Designated_Type;
5651 -------------------------------
5652 -- Matches_Limited_With_View --
5653 -------------------------------
5655 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean is
5657 -- In some cases a type imported through a limited_with clause, and
5658 -- its nonlimited view are both visible, for example in an anonymous
5659 -- access-to-class-wide type in a formal. Both entities designate the
5662 if From_With_Type (T1)
5663 and then T2 = Available_View (T1)
5667 elsif From_With_Type (T2)
5668 and then T1 = Available_View (T2)
5675 end Matches_Limited_With_View;
5677 -- Start of processing for Conforming_Types
5680 -- The context is an instance association for a formal
5681 -- access-to-subprogram type; the formal parameter types require
5682 -- mapping because they may denote other formal parameters of the
5686 Type_1 := Get_Instance_Of (T1);
5687 Type_2 := Get_Instance_Of (T2);
5690 -- If one of the types is a view of the other introduced by a limited
5691 -- with clause, treat these as conforming for all purposes.
5693 if Matches_Limited_With_View (T1, T2) then
5696 elsif Base_Types_Match (Type_1, Type_2) then
5697 return Ctype <= Mode_Conformant
5698 or else Subtypes_Statically_Match (Type_1, Type_2);
5700 elsif Is_Incomplete_Or_Private_Type (Type_1)
5701 and then Present (Full_View (Type_1))
5702 and then Base_Types_Match (Full_View (Type_1), Type_2)
5704 return Ctype <= Mode_Conformant
5705 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
5707 elsif Ekind (Type_2) = E_Incomplete_Type
5708 and then Present (Full_View (Type_2))
5709 and then Base_Types_Match (Type_1, Full_View (Type_2))
5711 return Ctype <= Mode_Conformant
5712 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
5714 elsif Is_Private_Type (Type_2)
5715 and then In_Instance
5716 and then Present (Full_View (Type_2))
5717 and then Base_Types_Match (Type_1, Full_View (Type_2))
5719 return Ctype <= Mode_Conformant
5720 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
5723 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
5724 -- treated recursively because they carry a signature.
5726 Are_Anonymous_Access_To_Subprogram_Types :=
5727 Ekind (Type_1) = Ekind (Type_2)
5729 (Ekind (Type_1) = E_Anonymous_Access_Subprogram_Type
5731 Ekind (Type_1) = E_Anonymous_Access_Protected_Subprogram_Type);
5733 -- Test anonymous access type case. For this case, static subtype
5734 -- matching is required for mode conformance (RM 6.3.1(15)). We check
5735 -- the base types because we may have built internal subtype entities
5736 -- to handle null-excluding types (see Process_Formals).
5738 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
5740 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
5741 or else Are_Anonymous_Access_To_Subprogram_Types -- Ada 2005 (AI-254)
5744 Desig_1 : Entity_Id;
5745 Desig_2 : Entity_Id;
5748 -- In Ada2005, access constant indicators must match for
5749 -- subtype conformance.
5751 if Ada_Version >= Ada_2005
5752 and then Ctype >= Subtype_Conformant
5754 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
5759 Desig_1 := Find_Designated_Type (Type_1);
5760 Desig_2 := Find_Designated_Type (Type_2);
5762 -- If the context is an instance association for a formal
5763 -- access-to-subprogram type; formal access parameter designated
5764 -- types require mapping because they may denote other formal
5765 -- parameters of the generic unit.
5768 Desig_1 := Get_Instance_Of (Desig_1);
5769 Desig_2 := Get_Instance_Of (Desig_2);
5772 -- It is possible for a Class_Wide_Type to be introduced for an
5773 -- incomplete type, in which case there is a separate class_ wide
5774 -- type for the full view. The types conform if their Etypes
5775 -- conform, i.e. one may be the full view of the other. This can
5776 -- only happen in the context of an access parameter, other uses
5777 -- of an incomplete Class_Wide_Type are illegal.
5779 if Is_Class_Wide_Type (Desig_1)
5781 Is_Class_Wide_Type (Desig_2)
5785 (Etype (Base_Type (Desig_1)),
5786 Etype (Base_Type (Desig_2)), Ctype);
5788 elsif Are_Anonymous_Access_To_Subprogram_Types then
5789 if Ada_Version < Ada_2005 then
5790 return Ctype = Type_Conformant
5792 Subtypes_Statically_Match (Desig_1, Desig_2);
5794 -- We must check the conformance of the signatures themselves
5798 Conformant : Boolean;
5801 (Desig_1, Desig_2, Ctype, False, Conformant);
5807 return Base_Type (Desig_1) = Base_Type (Desig_2)
5808 and then (Ctype = Type_Conformant
5810 Subtypes_Statically_Match (Desig_1, Desig_2));
5814 -- Otherwise definitely no match
5817 if ((Ekind (Type_1) = E_Anonymous_Access_Type
5818 and then Is_Access_Type (Type_2))
5819 or else (Ekind (Type_2) = E_Anonymous_Access_Type
5820 and then Is_Access_Type (Type_1)))
5823 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
5825 May_Hide_Profile := True;
5830 end Conforming_Types;
5832 --------------------------
5833 -- Create_Extra_Formals --
5834 --------------------------
5836 procedure Create_Extra_Formals (E : Entity_Id) is
5838 First_Extra : Entity_Id := Empty;
5839 Last_Extra : Entity_Id;
5840 Formal_Type : Entity_Id;
5841 P_Formal : Entity_Id := Empty;
5843 function Add_Extra_Formal
5844 (Assoc_Entity : Entity_Id;
5847 Suffix : String) return Entity_Id;
5848 -- Add an extra formal to the current list of formals and extra formals.
5849 -- The extra formal is added to the end of the list of extra formals,
5850 -- and also returned as the result. These formals are always of mode IN.
5851 -- The new formal has the type Typ, is declared in Scope, and its name
5852 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
5853 -- The following suffixes are currently used. They should not be changed
5854 -- without coordinating with CodePeer, which makes use of these to
5855 -- provide better messages.
5857 -- O denotes the Constrained bit.
5858 -- L denotes the accessibility level.
5859 -- BIP_xxx denotes an extra formal for a build-in-place function. See
5860 -- the full list in exp_ch6.BIP_Formal_Kind.
5862 ----------------------
5863 -- Add_Extra_Formal --
5864 ----------------------
5866 function Add_Extra_Formal
5867 (Assoc_Entity : Entity_Id;
5870 Suffix : String) return Entity_Id
5872 EF : constant Entity_Id :=
5873 Make_Defining_Identifier (Sloc (Assoc_Entity),
5874 Chars => New_External_Name (Chars (Assoc_Entity),
5878 -- A little optimization. Never generate an extra formal for the
5879 -- _init operand of an initialization procedure, since it could
5882 if Chars (Formal) = Name_uInit then
5886 Set_Ekind (EF, E_In_Parameter);
5887 Set_Actual_Subtype (EF, Typ);
5888 Set_Etype (EF, Typ);
5889 Set_Scope (EF, Scope);
5890 Set_Mechanism (EF, Default_Mechanism);
5891 Set_Formal_Validity (EF);
5893 if No (First_Extra) then
5895 Set_Extra_Formals (Scope, First_Extra);
5898 if Present (Last_Extra) then
5899 Set_Extra_Formal (Last_Extra, EF);
5905 end Add_Extra_Formal;
5907 -- Start of processing for Create_Extra_Formals
5910 -- We never generate extra formals if expansion is not active
5911 -- because we don't need them unless we are generating code.
5913 if not Expander_Active then
5917 -- If this is a derived subprogram then the subtypes of the parent
5918 -- subprogram's formal parameters will be used to determine the need
5919 -- for extra formals.
5921 if Is_Overloadable (E) and then Present (Alias (E)) then
5922 P_Formal := First_Formal (Alias (E));
5925 Last_Extra := Empty;
5926 Formal := First_Formal (E);
5927 while Present (Formal) loop
5928 Last_Extra := Formal;
5929 Next_Formal (Formal);
5932 -- If Extra_formals were already created, don't do it again. This
5933 -- situation may arise for subprogram types created as part of
5934 -- dispatching calls (see Expand_Dispatching_Call)
5936 if Present (Last_Extra) and then
5937 Present (Extra_Formal (Last_Extra))
5942 -- If the subprogram is a predefined dispatching subprogram then don't
5943 -- generate any extra constrained or accessibility level formals. In
5944 -- general we suppress these for internal subprograms (by not calling
5945 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
5946 -- generated stream attributes do get passed through because extra
5947 -- build-in-place formals are needed in some cases (limited 'Input).
5949 if Is_Predefined_Internal_Operation (E) then
5950 goto Test_For_BIP_Extras;
5953 Formal := First_Formal (E);
5954 while Present (Formal) loop
5956 -- Create extra formal for supporting the attribute 'Constrained.
5957 -- The case of a private type view without discriminants also
5958 -- requires the extra formal if the underlying type has defaulted
5961 if Ekind (Formal) /= E_In_Parameter then
5962 if Present (P_Formal) then
5963 Formal_Type := Etype (P_Formal);
5965 Formal_Type := Etype (Formal);
5968 -- Do not produce extra formals for Unchecked_Union parameters.
5969 -- Jump directly to the end of the loop.
5971 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
5972 goto Skip_Extra_Formal_Generation;
5975 if not Has_Discriminants (Formal_Type)
5976 and then Ekind (Formal_Type) in Private_Kind
5977 and then Present (Underlying_Type (Formal_Type))
5979 Formal_Type := Underlying_Type (Formal_Type);
5982 -- Suppress the extra formal if formal's subtype is constrained or
5983 -- indefinite, or we're compiling for Ada 2012 and the underlying
5984 -- type is tagged and limited. In Ada 2012, a limited tagged type
5985 -- can have defaulted discriminants, but 'Constrained is required
5986 -- to return True, so the formal is never needed (see AI05-0214).
5987 -- Note that this ensures consistency of calling sequences for
5988 -- dispatching operations when some types in a class have defaults
5989 -- on discriminants and others do not (and requiring the extra
5990 -- formal would introduce distributed overhead).
5992 if Has_Discriminants (Formal_Type)
5993 and then not Is_Constrained (Formal_Type)
5994 and then not Is_Indefinite_Subtype (Formal_Type)
5995 and then (Ada_Version < Ada_2012
5997 not (Is_Tagged_Type (Underlying_Type (Formal_Type))
5998 and then Is_Limited_Type (Formal_Type)))
6000 Set_Extra_Constrained
6001 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
6005 -- Create extra formal for supporting accessibility checking. This
6006 -- is done for both anonymous access formals and formals of named
6007 -- access types that are marked as controlling formals. The latter
6008 -- case can occur when Expand_Dispatching_Call creates a subprogram
6009 -- type and substitutes the types of access-to-class-wide actuals
6010 -- for the anonymous access-to-specific-type of controlling formals.
6011 -- Base_Type is applied because in cases where there is a null
6012 -- exclusion the formal may have an access subtype.
6014 -- This is suppressed if we specifically suppress accessibility
6015 -- checks at the package level for either the subprogram, or the
6016 -- package in which it resides. However, we do not suppress it
6017 -- simply if the scope has accessibility checks suppressed, since
6018 -- this could cause trouble when clients are compiled with a
6019 -- different suppression setting. The explicit checks at the
6020 -- package level are safe from this point of view.
6022 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
6023 or else (Is_Controlling_Formal (Formal)
6024 and then Is_Access_Type (Base_Type (Etype (Formal)))))
6026 (Explicit_Suppress (E, Accessibility_Check)
6028 Explicit_Suppress (Scope (E), Accessibility_Check))
6031 or else Present (Extra_Accessibility (P_Formal)))
6033 Set_Extra_Accessibility
6034 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
6037 -- This label is required when skipping extra formal generation for
6038 -- Unchecked_Union parameters.
6040 <<Skip_Extra_Formal_Generation>>
6042 if Present (P_Formal) then
6043 Next_Formal (P_Formal);
6046 Next_Formal (Formal);
6049 <<Test_For_BIP_Extras>>
6051 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
6052 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
6054 if Ada_Version >= Ada_2005 and then Is_Build_In_Place_Function (E) then
6056 Result_Subt : constant Entity_Id := Etype (E);
6058 Discard : Entity_Id;
6059 pragma Warnings (Off, Discard);
6062 -- In the case of functions with unconstrained result subtypes,
6063 -- add a 4-state formal indicating whether the return object is
6064 -- allocated by the caller (1), or should be allocated by the
6065 -- callee on the secondary stack (2), in the global heap (3), or
6066 -- in a user-defined storage pool (4). For the moment we just use
6067 -- Natural for the type of this formal. Note that this formal
6068 -- isn't usually needed in the case where the result subtype is
6069 -- constrained, but it is needed when the function has a tagged
6070 -- result, because generally such functions can be called in a
6071 -- dispatching context and such calls must be handled like calls
6072 -- to a class-wide function.
6074 if not Is_Constrained (Underlying_Type (Result_Subt))
6075 or else Is_Tagged_Type (Underlying_Type (Result_Subt))
6079 (E, Standard_Natural,
6080 E, BIP_Formal_Suffix (BIP_Alloc_Form));
6083 -- In the case of functions whose result type needs finalization,
6084 -- add an extra formal of type Ada.Finalization.Heap_Management.
6085 -- Finalization_Collection_Ptr.
6087 if Needs_BIP_Collection (E) then
6090 (E, RTE (RE_Finalization_Collection_Ptr),
6091 E, BIP_Formal_Suffix (BIP_Collection));
6094 -- If the result type contains tasks, we have two extra formals:
6095 -- the master of the tasks to be created, and the caller's
6096 -- activation chain.
6098 if Has_Task (Result_Subt) then
6101 (E, RTE (RE_Master_Id),
6102 E, BIP_Formal_Suffix (BIP_Master));
6105 (E, RTE (RE_Activation_Chain_Access),
6106 E, BIP_Formal_Suffix (BIP_Activation_Chain));
6109 -- All build-in-place functions get an extra formal that will be
6110 -- passed the address of the return object within the caller.
6113 Formal_Type : constant Entity_Id :=
6115 (E_Anonymous_Access_Type, E,
6116 Scope_Id => Scope (E));
6118 Set_Directly_Designated_Type (Formal_Type, Result_Subt);
6119 Set_Etype (Formal_Type, Formal_Type);
6120 Set_Depends_On_Private
6121 (Formal_Type, Has_Private_Component (Formal_Type));
6122 Set_Is_Public (Formal_Type, Is_Public (Scope (Formal_Type)));
6123 Set_Is_Access_Constant (Formal_Type, False);
6125 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
6126 -- the designated type comes from the limited view (for
6127 -- back-end purposes).
6129 Set_From_With_Type (Formal_Type, From_With_Type (Result_Subt));
6131 Layout_Type (Formal_Type);
6135 (E, Formal_Type, E, BIP_Formal_Suffix (BIP_Object_Access));
6139 end Create_Extra_Formals;
6141 -----------------------------
6142 -- Enter_Overloaded_Entity --
6143 -----------------------------
6145 procedure Enter_Overloaded_Entity (S : Entity_Id) is
6146 E : Entity_Id := Current_Entity_In_Scope (S);
6147 C_E : Entity_Id := Current_Entity (S);
6151 Set_Has_Homonym (E);
6152 Set_Has_Homonym (S);
6155 Set_Is_Immediately_Visible (S);
6156 Set_Scope (S, Current_Scope);
6158 -- Chain new entity if front of homonym in current scope, so that
6159 -- homonyms are contiguous.
6164 while Homonym (C_E) /= E loop
6165 C_E := Homonym (C_E);
6168 Set_Homonym (C_E, S);
6172 Set_Current_Entity (S);
6177 Append_Entity (S, Current_Scope);
6178 Set_Public_Status (S);
6180 if Debug_Flag_E then
6181 Write_Str ("New overloaded entity chain: ");
6182 Write_Name (Chars (S));
6185 while Present (E) loop
6186 Write_Str (" "); Write_Int (Int (E));
6193 -- Generate warning for hiding
6196 and then Comes_From_Source (S)
6197 and then In_Extended_Main_Source_Unit (S)
6204 -- Warn unless genuine overloading. Do not emit warning on
6205 -- hiding predefined operators in Standard (these are either an
6206 -- (artifact of our implicit declarations, or simple noise) but
6207 -- keep warning on a operator defined on a local subtype, because
6208 -- of the real danger that different operators may be applied in
6209 -- various parts of the program.
6211 -- Note that if E and S have the same scope, there is never any
6212 -- hiding. Either the two conflict, and the program is illegal,
6213 -- or S is overriding an implicit inherited subprogram.
6215 if Scope (E) /= Scope (S)
6216 and then (not Is_Overloadable (E)
6217 or else Subtype_Conformant (E, S))
6218 and then (Is_Immediately_Visible (E)
6220 Is_Potentially_Use_Visible (S))
6222 if Scope (E) /= Standard_Standard then
6223 Error_Msg_Sloc := Sloc (E);
6224 Error_Msg_N ("declaration of & hides one#?", S);
6226 elsif Nkind (S) = N_Defining_Operator_Symbol
6228 Scope (Base_Type (Etype (First_Formal (S)))) /= Scope (S)
6231 ("declaration of & hides predefined operator?", S);
6236 end Enter_Overloaded_Entity;
6238 -----------------------------
6239 -- Check_Untagged_Equality --
6240 -----------------------------
6242 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
6243 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
6244 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
6248 if Nkind (Decl) = N_Subprogram_Declaration
6249 and then Is_Record_Type (Typ)
6250 and then not Is_Tagged_Type (Typ)
6252 -- If the type is not declared in a package, or if we are in the
6253 -- body of the package or in some other scope, the new operation is
6254 -- not primitive, and therefore legal, though suspicious. If the
6255 -- type is a generic actual (sub)type, the operation is not primitive
6256 -- either because the base type is declared elsewhere.
6258 if Is_Frozen (Typ) then
6259 if Ekind (Scope (Typ)) /= E_Package
6260 or else Scope (Typ) /= Current_Scope
6264 elsif Is_Generic_Actual_Type (Typ) then
6267 elsif In_Package_Body (Scope (Typ)) then
6269 ("equality operator must be declared "
6270 & "before type& is frozen", Eq_Op, Typ);
6272 ("\move declaration to package spec", Eq_Op);
6276 ("equality operator must be declared "
6277 & "before type& is frozen", Eq_Op, Typ);
6279 Obj_Decl := Next (Parent (Typ));
6280 while Present (Obj_Decl)
6281 and then Obj_Decl /= Decl
6283 if Nkind (Obj_Decl) = N_Object_Declaration
6284 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
6286 Error_Msg_NE ("type& is frozen by declaration?",
6289 ("\an equality operator cannot be declared after this "
6290 & "point (RM 4.5.2 (9.8)) (Ada 2012))?", Obj_Decl);
6298 elsif not In_Same_List (Parent (Typ), Decl)
6299 and then not Is_Limited_Type (Typ)
6302 -- This makes it illegal to have a primitive equality declared in
6303 -- the private part if the type is visible.
6305 Error_Msg_N ("equality operator appears too late", Eq_Op);
6308 end Check_Untagged_Equality;
6310 -----------------------------
6311 -- Find_Corresponding_Spec --
6312 -----------------------------
6314 function Find_Corresponding_Spec
6316 Post_Error : Boolean := True) return Entity_Id
6318 Spec : constant Node_Id := Specification (N);
6319 Designator : constant Entity_Id := Defining_Entity (Spec);
6324 E := Current_Entity (Designator);
6325 while Present (E) loop
6327 -- We are looking for a matching spec. It must have the same scope,
6328 -- and the same name, and either be type conformant, or be the case
6329 -- of a library procedure spec and its body (which belong to one
6330 -- another regardless of whether they are type conformant or not).
6332 if Scope (E) = Current_Scope then
6333 if Current_Scope = Standard_Standard
6334 or else (Ekind (E) = Ekind (Designator)
6335 and then Type_Conformant (E, Designator))
6337 -- Within an instantiation, we know that spec and body are
6338 -- subtype conformant, because they were subtype conformant
6339 -- in the generic. We choose the subtype-conformant entity
6340 -- here as well, to resolve spurious ambiguities in the
6341 -- instance that were not present in the generic (i.e. when
6342 -- two different types are given the same actual). If we are
6343 -- looking for a spec to match a body, full conformance is
6347 Set_Convention (Designator, Convention (E));
6349 -- Skip past subprogram bodies and subprogram renamings that
6350 -- may appear to have a matching spec, but that aren't fully
6351 -- conformant with it. That can occur in cases where an
6352 -- actual type causes unrelated homographs in the instance.
6354 if Nkind_In (N, N_Subprogram_Body,
6355 N_Subprogram_Renaming_Declaration)
6356 and then Present (Homonym (E))
6357 and then not Fully_Conformant (Designator, E)
6361 elsif not Subtype_Conformant (Designator, E) then
6366 if not Has_Completion (E) then
6367 if Nkind (N) /= N_Subprogram_Body_Stub then
6368 Set_Corresponding_Spec (N, E);
6371 Set_Has_Completion (E);
6374 elsif Nkind (Parent (N)) = N_Subunit then
6376 -- If this is the proper body of a subunit, the completion
6377 -- flag is set when analyzing the stub.
6381 -- If E is an internal function with a controlling result
6382 -- that was created for an operation inherited by a null
6383 -- extension, it may be overridden by a body without a previous
6384 -- spec (one more reason why these should be shunned). In that
6385 -- case remove the generated body if present, because the
6386 -- current one is the explicit overriding.
6388 elsif Ekind (E) = E_Function
6389 and then Ada_Version >= Ada_2005
6390 and then not Comes_From_Source (E)
6391 and then Has_Controlling_Result (E)
6392 and then Is_Null_Extension (Etype (E))
6393 and then Comes_From_Source (Spec)
6395 Set_Has_Completion (E, False);
6398 and then Nkind (Parent (E)) = N_Function_Specification
6401 (Unit_Declaration_Node
6402 (Corresponding_Body (Unit_Declaration_Node (E))));
6406 -- If expansion is disabled, or if the wrapper function has
6407 -- not been generated yet, this a late body overriding an
6408 -- inherited operation, or it is an overriding by some other
6409 -- declaration before the controlling result is frozen. In
6410 -- either case this is a declaration of a new entity.
6416 -- If the body already exists, then this is an error unless
6417 -- the previous declaration is the implicit declaration of a
6418 -- derived subprogram. It is also legal for an instance to
6419 -- contain type conformant overloadable declarations (but the
6420 -- generic declaration may not), per 8.3(26/2).
6422 elsif No (Alias (E))
6423 and then not Is_Intrinsic_Subprogram (E)
6424 and then not In_Instance
6427 Error_Msg_Sloc := Sloc (E);
6429 if Is_Imported (E) then
6431 ("body not allowed for imported subprogram & declared#",
6434 Error_Msg_NE ("duplicate body for & declared#", N, E);
6438 -- Child units cannot be overloaded, so a conformance mismatch
6439 -- between body and a previous spec is an error.
6441 elsif Is_Child_Unit (E)
6443 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
6445 Nkind (Parent (Unit_Declaration_Node (Designator))) =
6450 ("body of child unit does not match previous declaration", N);
6458 -- On exit, we know that no previous declaration of subprogram exists
6461 end Find_Corresponding_Spec;
6463 ----------------------
6464 -- Fully_Conformant --
6465 ----------------------
6467 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
6470 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
6472 end Fully_Conformant;
6474 ----------------------------------
6475 -- Fully_Conformant_Expressions --
6476 ----------------------------------
6478 function Fully_Conformant_Expressions
6479 (Given_E1 : Node_Id;
6480 Given_E2 : Node_Id) return Boolean
6482 E1 : constant Node_Id := Original_Node (Given_E1);
6483 E2 : constant Node_Id := Original_Node (Given_E2);
6484 -- We always test conformance on original nodes, since it is possible
6485 -- for analysis and/or expansion to make things look as though they
6486 -- conform when they do not, e.g. by converting 1+2 into 3.
6488 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
6489 renames Fully_Conformant_Expressions;
6491 function FCL (L1, L2 : List_Id) return Boolean;
6492 -- Compare elements of two lists for conformance. Elements have to
6493 -- be conformant, and actuals inserted as default parameters do not
6494 -- match explicit actuals with the same value.
6496 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
6497 -- Compare an operator node with a function call
6503 function FCL (L1, L2 : List_Id) return Boolean is
6507 if L1 = No_List then
6513 if L2 = No_List then
6519 -- Compare two lists, skipping rewrite insertions (we want to
6520 -- compare the original trees, not the expanded versions!)
6523 if Is_Rewrite_Insertion (N1) then
6525 elsif Is_Rewrite_Insertion (N2) then
6531 elsif not FCE (N1, N2) then
6544 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
6545 Actuals : constant List_Id := Parameter_Associations (Call_Node);
6550 or else Entity (Op_Node) /= Entity (Name (Call_Node))
6555 Act := First (Actuals);
6557 if Nkind (Op_Node) in N_Binary_Op then
6558 if not FCE (Left_Opnd (Op_Node), Act) then
6565 return Present (Act)
6566 and then FCE (Right_Opnd (Op_Node), Act)
6567 and then No (Next (Act));
6571 -- Start of processing for Fully_Conformant_Expressions
6574 -- Non-conformant if paren count does not match. Note: if some idiot
6575 -- complains that we don't do this right for more than 3 levels of
6576 -- parentheses, they will be treated with the respect they deserve!
6578 if Paren_Count (E1) /= Paren_Count (E2) then
6581 -- If same entities are referenced, then they are conformant even if
6582 -- they have different forms (RM 8.3.1(19-20)).
6584 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
6585 if Present (Entity (E1)) then
6586 return Entity (E1) = Entity (E2)
6587 or else (Chars (Entity (E1)) = Chars (Entity (E2))
6588 and then Ekind (Entity (E1)) = E_Discriminant
6589 and then Ekind (Entity (E2)) = E_In_Parameter);
6591 elsif Nkind (E1) = N_Expanded_Name
6592 and then Nkind (E2) = N_Expanded_Name
6593 and then Nkind (Selector_Name (E1)) = N_Character_Literal
6594 and then Nkind (Selector_Name (E2)) = N_Character_Literal
6596 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
6599 -- Identifiers in component associations don't always have
6600 -- entities, but their names must conform.
6602 return Nkind (E1) = N_Identifier
6603 and then Nkind (E2) = N_Identifier
6604 and then Chars (E1) = Chars (E2);
6607 elsif Nkind (E1) = N_Character_Literal
6608 and then Nkind (E2) = N_Expanded_Name
6610 return Nkind (Selector_Name (E2)) = N_Character_Literal
6611 and then Chars (E1) = Chars (Selector_Name (E2));
6613 elsif Nkind (E2) = N_Character_Literal
6614 and then Nkind (E1) = N_Expanded_Name
6616 return Nkind (Selector_Name (E1)) = N_Character_Literal
6617 and then Chars (E2) = Chars (Selector_Name (E1));
6619 elsif Nkind (E1) in N_Op
6620 and then Nkind (E2) = N_Function_Call
6622 return FCO (E1, E2);
6624 elsif Nkind (E2) in N_Op
6625 and then Nkind (E1) = N_Function_Call
6627 return FCO (E2, E1);
6629 -- Otherwise we must have the same syntactic entity
6631 elsif Nkind (E1) /= Nkind (E2) then
6634 -- At this point, we specialize by node type
6641 FCL (Expressions (E1), Expressions (E2))
6643 FCL (Component_Associations (E1),
6644 Component_Associations (E2));
6647 if Nkind (Expression (E1)) = N_Qualified_Expression
6649 Nkind (Expression (E2)) = N_Qualified_Expression
6651 return FCE (Expression (E1), Expression (E2));
6653 -- Check that the subtype marks and any constraints
6658 Indic1 : constant Node_Id := Expression (E1);
6659 Indic2 : constant Node_Id := Expression (E2);
6664 if Nkind (Indic1) /= N_Subtype_Indication then
6666 Nkind (Indic2) /= N_Subtype_Indication
6667 and then Entity (Indic1) = Entity (Indic2);
6669 elsif Nkind (Indic2) /= N_Subtype_Indication then
6671 Nkind (Indic1) /= N_Subtype_Indication
6672 and then Entity (Indic1) = Entity (Indic2);
6675 if Entity (Subtype_Mark (Indic1)) /=
6676 Entity (Subtype_Mark (Indic2))
6681 Elt1 := First (Constraints (Constraint (Indic1)));
6682 Elt2 := First (Constraints (Constraint (Indic2)));
6683 while Present (Elt1) and then Present (Elt2) loop
6684 if not FCE (Elt1, Elt2) then
6697 when N_Attribute_Reference =>
6699 Attribute_Name (E1) = Attribute_Name (E2)
6700 and then FCL (Expressions (E1), Expressions (E2));
6704 Entity (E1) = Entity (E2)
6705 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
6706 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
6708 when N_Short_Circuit | N_Membership_Test =>
6710 FCE (Left_Opnd (E1), Left_Opnd (E2))
6712 FCE (Right_Opnd (E1), Right_Opnd (E2));
6714 when N_Case_Expression =>
6720 if not FCE (Expression (E1), Expression (E2)) then
6724 Alt1 := First (Alternatives (E1));
6725 Alt2 := First (Alternatives (E2));
6727 if Present (Alt1) /= Present (Alt2) then
6729 elsif No (Alt1) then
6733 if not FCE (Expression (Alt1), Expression (Alt2))
6734 or else not FCL (Discrete_Choices (Alt1),
6735 Discrete_Choices (Alt2))
6746 when N_Character_Literal =>
6748 Char_Literal_Value (E1) = Char_Literal_Value (E2);
6750 when N_Component_Association =>
6752 FCL (Choices (E1), Choices (E2))
6754 FCE (Expression (E1), Expression (E2));
6756 when N_Conditional_Expression =>
6758 FCL (Expressions (E1), Expressions (E2));
6760 when N_Explicit_Dereference =>
6762 FCE (Prefix (E1), Prefix (E2));
6764 when N_Extension_Aggregate =>
6766 FCL (Expressions (E1), Expressions (E2))
6767 and then Null_Record_Present (E1) =
6768 Null_Record_Present (E2)
6769 and then FCL (Component_Associations (E1),
6770 Component_Associations (E2));
6772 when N_Function_Call =>
6774 FCE (Name (E1), Name (E2))
6776 FCL (Parameter_Associations (E1),
6777 Parameter_Associations (E2));
6779 when N_Indexed_Component =>
6781 FCE (Prefix (E1), Prefix (E2))
6783 FCL (Expressions (E1), Expressions (E2));
6785 when N_Integer_Literal =>
6786 return (Intval (E1) = Intval (E2));
6791 when N_Operator_Symbol =>
6793 Chars (E1) = Chars (E2);
6795 when N_Others_Choice =>
6798 when N_Parameter_Association =>
6800 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
6801 and then FCE (Explicit_Actual_Parameter (E1),
6802 Explicit_Actual_Parameter (E2));
6804 when N_Qualified_Expression =>
6806 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
6808 FCE (Expression (E1), Expression (E2));
6810 when N_Quantified_Expression =>
6811 if not FCE (Condition (E1), Condition (E2)) then
6815 if Present (Loop_Parameter_Specification (E1))
6816 and then Present (Loop_Parameter_Specification (E2))
6819 L1 : constant Node_Id :=
6820 Loop_Parameter_Specification (E1);
6821 L2 : constant Node_Id :=
6822 Loop_Parameter_Specification (E2);
6826 Reverse_Present (L1) = Reverse_Present (L2)
6828 FCE (Defining_Identifier (L1),
6829 Defining_Identifier (L2))
6831 FCE (Discrete_Subtype_Definition (L1),
6832 Discrete_Subtype_Definition (L2));
6835 else -- quantified expression with an iterator
6837 I1 : constant Node_Id := Iterator_Specification (E1);
6838 I2 : constant Node_Id := Iterator_Specification (E2);
6842 FCE (Defining_Identifier (I1),
6843 Defining_Identifier (I2))
6845 Of_Present (I1) = Of_Present (I2)
6847 Reverse_Present (I1) = Reverse_Present (I2)
6848 and then FCE (Name (I1), Name (I2))
6849 and then FCE (Subtype_Indication (I1),
6850 Subtype_Indication (I2));
6856 FCE (Low_Bound (E1), Low_Bound (E2))
6858 FCE (High_Bound (E1), High_Bound (E2));
6860 when N_Real_Literal =>
6861 return (Realval (E1) = Realval (E2));
6863 when N_Selected_Component =>
6865 FCE (Prefix (E1), Prefix (E2))
6867 FCE (Selector_Name (E1), Selector_Name (E2));
6871 FCE (Prefix (E1), Prefix (E2))
6873 FCE (Discrete_Range (E1), Discrete_Range (E2));
6875 when N_String_Literal =>
6877 S1 : constant String_Id := Strval (E1);
6878 S2 : constant String_Id := Strval (E2);
6879 L1 : constant Nat := String_Length (S1);
6880 L2 : constant Nat := String_Length (S2);
6887 for J in 1 .. L1 loop
6888 if Get_String_Char (S1, J) /=
6889 Get_String_Char (S2, J)
6899 when N_Type_Conversion =>
6901 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
6903 FCE (Expression (E1), Expression (E2));
6907 Entity (E1) = Entity (E2)
6909 FCE (Right_Opnd (E1), Right_Opnd (E2));
6911 when N_Unchecked_Type_Conversion =>
6913 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
6915 FCE (Expression (E1), Expression (E2));
6917 -- All other node types cannot appear in this context. Strictly
6918 -- we should raise a fatal internal error. Instead we just ignore
6919 -- the nodes. This means that if anyone makes a mistake in the
6920 -- expander and mucks an expression tree irretrievably, the
6921 -- result will be a failure to detect a (probably very obscure)
6922 -- case of non-conformance, which is better than bombing on some
6923 -- case where two expressions do in fact conform.
6930 end Fully_Conformant_Expressions;
6932 ----------------------------------------
6933 -- Fully_Conformant_Discrete_Subtypes --
6934 ----------------------------------------
6936 function Fully_Conformant_Discrete_Subtypes
6937 (Given_S1 : Node_Id;
6938 Given_S2 : Node_Id) return Boolean
6940 S1 : constant Node_Id := Original_Node (Given_S1);
6941 S2 : constant Node_Id := Original_Node (Given_S2);
6943 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
6944 -- Special-case for a bound given by a discriminant, which in the body
6945 -- is replaced with the discriminal of the enclosing type.
6947 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
6948 -- Check both bounds
6950 -----------------------
6951 -- Conforming_Bounds --
6952 -----------------------
6954 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
6956 if Is_Entity_Name (B1)
6957 and then Is_Entity_Name (B2)
6958 and then Ekind (Entity (B1)) = E_Discriminant
6960 return Chars (B1) = Chars (B2);
6963 return Fully_Conformant_Expressions (B1, B2);
6965 end Conforming_Bounds;
6967 -----------------------
6968 -- Conforming_Ranges --
6969 -----------------------
6971 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
6974 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
6976 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
6977 end Conforming_Ranges;
6979 -- Start of processing for Fully_Conformant_Discrete_Subtypes
6982 if Nkind (S1) /= Nkind (S2) then
6985 elsif Is_Entity_Name (S1) then
6986 return Entity (S1) = Entity (S2);
6988 elsif Nkind (S1) = N_Range then
6989 return Conforming_Ranges (S1, S2);
6991 elsif Nkind (S1) = N_Subtype_Indication then
6993 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
6996 (Range_Expression (Constraint (S1)),
6997 Range_Expression (Constraint (S2)));
7001 end Fully_Conformant_Discrete_Subtypes;
7003 --------------------
7004 -- Install_Entity --
7005 --------------------
7007 procedure Install_Entity (E : Entity_Id) is
7008 Prev : constant Entity_Id := Current_Entity (E);
7010 Set_Is_Immediately_Visible (E);
7011 Set_Current_Entity (E);
7012 Set_Homonym (E, Prev);
7015 ---------------------
7016 -- Install_Formals --
7017 ---------------------
7019 procedure Install_Formals (Id : Entity_Id) is
7022 F := First_Formal (Id);
7023 while Present (F) loop
7027 end Install_Formals;
7029 -----------------------------
7030 -- Is_Interface_Conformant --
7031 -----------------------------
7033 function Is_Interface_Conformant
7034 (Tagged_Type : Entity_Id;
7035 Iface_Prim : Entity_Id;
7036 Prim : Entity_Id) return Boolean
7038 Iface : constant Entity_Id := Find_Dispatching_Type (Iface_Prim);
7039 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
7042 pragma Assert (Is_Subprogram (Iface_Prim)
7043 and then Is_Subprogram (Prim)
7044 and then Is_Dispatching_Operation (Iface_Prim)
7045 and then Is_Dispatching_Operation (Prim));
7047 pragma Assert (Is_Interface (Iface)
7048 or else (Present (Alias (Iface_Prim))
7051 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
7053 if Prim = Iface_Prim
7054 or else not Is_Subprogram (Prim)
7055 or else Ekind (Prim) /= Ekind (Iface_Prim)
7056 or else not Is_Dispatching_Operation (Prim)
7057 or else Scope (Prim) /= Scope (Tagged_Type)
7059 or else Base_Type (Typ) /= Tagged_Type
7060 or else not Primitive_Names_Match (Iface_Prim, Prim)
7064 -- Case of a procedure, or a function that does not have a controlling
7065 -- result (I or access I).
7067 elsif Ekind (Iface_Prim) = E_Procedure
7068 or else Etype (Prim) = Etype (Iface_Prim)
7069 or else not Has_Controlling_Result (Prim)
7071 return Type_Conformant
7072 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
7074 -- Case of a function returning an interface, or an access to one.
7075 -- Check that the return types correspond.
7077 elsif Implements_Interface (Typ, Iface) then
7078 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
7080 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
7085 Type_Conformant (Prim, Iface_Prim,
7086 Skip_Controlling_Formals => True);
7092 end Is_Interface_Conformant;
7094 ---------------------------------
7095 -- Is_Non_Overriding_Operation --
7096 ---------------------------------
7098 function Is_Non_Overriding_Operation
7099 (Prev_E : Entity_Id;
7100 New_E : Entity_Id) return Boolean
7104 G_Typ : Entity_Id := Empty;
7106 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
7107 -- If F_Type is a derived type associated with a generic actual subtype,
7108 -- then return its Generic_Parent_Type attribute, else return Empty.
7110 function Types_Correspond
7111 (P_Type : Entity_Id;
7112 N_Type : Entity_Id) return Boolean;
7113 -- Returns true if and only if the types (or designated types in the
7114 -- case of anonymous access types) are the same or N_Type is derived
7115 -- directly or indirectly from P_Type.
7117 -----------------------------
7118 -- Get_Generic_Parent_Type --
7119 -----------------------------
7121 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
7126 if Is_Derived_Type (F_Typ)
7127 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
7129 -- The tree must be traversed to determine the parent subtype in
7130 -- the generic unit, which unfortunately isn't always available
7131 -- via semantic attributes. ??? (Note: The use of Original_Node
7132 -- is needed for cases where a full derived type has been
7135 Indic := Subtype_Indication
7136 (Type_Definition (Original_Node (Parent (F_Typ))));
7138 if Nkind (Indic) = N_Subtype_Indication then
7139 G_Typ := Entity (Subtype_Mark (Indic));
7141 G_Typ := Entity (Indic);
7144 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
7145 and then Present (Generic_Parent_Type (Parent (G_Typ)))
7147 return Generic_Parent_Type (Parent (G_Typ));
7152 end Get_Generic_Parent_Type;
7154 ----------------------
7155 -- Types_Correspond --
7156 ----------------------
7158 function Types_Correspond
7159 (P_Type : Entity_Id;
7160 N_Type : Entity_Id) return Boolean
7162 Prev_Type : Entity_Id := Base_Type (P_Type);
7163 New_Type : Entity_Id := Base_Type (N_Type);
7166 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
7167 Prev_Type := Designated_Type (Prev_Type);
7170 if Ekind (New_Type) = E_Anonymous_Access_Type then
7171 New_Type := Designated_Type (New_Type);
7174 if Prev_Type = New_Type then
7177 elsif not Is_Class_Wide_Type (New_Type) then
7178 while Etype (New_Type) /= New_Type loop
7179 New_Type := Etype (New_Type);
7180 if New_Type = Prev_Type then
7186 end Types_Correspond;
7188 -- Start of processing for Is_Non_Overriding_Operation
7191 -- In the case where both operations are implicit derived subprograms
7192 -- then neither overrides the other. This can only occur in certain
7193 -- obscure cases (e.g., derivation from homographs created in a generic
7196 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
7199 elsif Ekind (Current_Scope) = E_Package
7200 and then Is_Generic_Instance (Current_Scope)
7201 and then In_Private_Part (Current_Scope)
7202 and then Comes_From_Source (New_E)
7204 -- We examine the formals and result subtype of the inherited
7205 -- operation, to determine whether their type is derived from (the
7206 -- instance of) a generic type.
7208 Formal := First_Formal (Prev_E);
7209 while Present (Formal) loop
7210 F_Typ := Base_Type (Etype (Formal));
7212 if Ekind (F_Typ) = E_Anonymous_Access_Type then
7213 F_Typ := Designated_Type (F_Typ);
7216 G_Typ := Get_Generic_Parent_Type (F_Typ);
7218 Next_Formal (Formal);
7221 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
7222 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
7229 -- If the generic type is a private type, then the original operation
7230 -- was not overriding in the generic, because there was no primitive
7231 -- operation to override.
7233 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
7234 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
7235 N_Formal_Private_Type_Definition
7239 -- The generic parent type is the ancestor of a formal derived
7240 -- type declaration. We need to check whether it has a primitive
7241 -- operation that should be overridden by New_E in the generic.
7245 P_Formal : Entity_Id;
7246 N_Formal : Entity_Id;
7250 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
7253 while Present (Prim_Elt) loop
7254 P_Prim := Node (Prim_Elt);
7256 if Chars (P_Prim) = Chars (New_E)
7257 and then Ekind (P_Prim) = Ekind (New_E)
7259 P_Formal := First_Formal (P_Prim);
7260 N_Formal := First_Formal (New_E);
7261 while Present (P_Formal) and then Present (N_Formal) loop
7262 P_Typ := Etype (P_Formal);
7263 N_Typ := Etype (N_Formal);
7265 if not Types_Correspond (P_Typ, N_Typ) then
7269 Next_Entity (P_Formal);
7270 Next_Entity (N_Formal);
7273 -- Found a matching primitive operation belonging to the
7274 -- formal ancestor type, so the new subprogram is
7278 and then No (N_Formal)
7279 and then (Ekind (New_E) /= E_Function
7282 (Etype (P_Prim), Etype (New_E)))
7288 Next_Elmt (Prim_Elt);
7291 -- If no match found, then the new subprogram does not
7292 -- override in the generic (nor in the instance).
7300 end Is_Non_Overriding_Operation;
7302 -------------------------------------
7303 -- List_Inherited_Pre_Post_Aspects --
7304 -------------------------------------
7306 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
7308 if Opt.List_Inherited_Aspects
7309 and then (Is_Subprogram (E) or else Is_Generic_Subprogram (E))
7312 Inherited : constant Subprogram_List :=
7313 Inherited_Subprograms (E);
7317 for J in Inherited'Range loop
7318 P := Spec_PPC_List (Contract (Inherited (J)));
7320 while Present (P) loop
7321 Error_Msg_Sloc := Sloc (P);
7323 if Class_Present (P) and then not Split_PPC (P) then
7324 if Pragma_Name (P) = Name_Precondition then
7326 ("?info: & inherits `Pre''Class` aspect from #", E);
7329 ("?info: & inherits `Post''Class` aspect from #", E);
7333 P := Next_Pragma (P);
7338 end List_Inherited_Pre_Post_Aspects;
7340 ------------------------------
7341 -- Make_Inequality_Operator --
7342 ------------------------------
7344 -- S is the defining identifier of an equality operator. We build a
7345 -- subprogram declaration with the right signature. This operation is
7346 -- intrinsic, because it is always expanded as the negation of the
7347 -- call to the equality function.
7349 procedure Make_Inequality_Operator (S : Entity_Id) is
7350 Loc : constant Source_Ptr := Sloc (S);
7353 Op_Name : Entity_Id;
7355 FF : constant Entity_Id := First_Formal (S);
7356 NF : constant Entity_Id := Next_Formal (FF);
7359 -- Check that equality was properly defined, ignore call if not
7366 A : constant Entity_Id :=
7367 Make_Defining_Identifier (Sloc (FF),
7368 Chars => Chars (FF));
7370 B : constant Entity_Id :=
7371 Make_Defining_Identifier (Sloc (NF),
7372 Chars => Chars (NF));
7375 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
7377 Formals := New_List (
7378 Make_Parameter_Specification (Loc,
7379 Defining_Identifier => A,
7381 New_Reference_To (Etype (First_Formal (S)),
7382 Sloc (Etype (First_Formal (S))))),
7384 Make_Parameter_Specification (Loc,
7385 Defining_Identifier => B,
7387 New_Reference_To (Etype (Next_Formal (First_Formal (S))),
7388 Sloc (Etype (Next_Formal (First_Formal (S)))))));
7391 Make_Subprogram_Declaration (Loc,
7393 Make_Function_Specification (Loc,
7394 Defining_Unit_Name => Op_Name,
7395 Parameter_Specifications => Formals,
7396 Result_Definition =>
7397 New_Reference_To (Standard_Boolean, Loc)));
7399 -- Insert inequality right after equality if it is explicit or after
7400 -- the derived type when implicit. These entities are created only
7401 -- for visibility purposes, and eventually replaced in the course of
7402 -- expansion, so they do not need to be attached to the tree and seen
7403 -- by the back-end. Keeping them internal also avoids spurious
7404 -- freezing problems. The declaration is inserted in the tree for
7405 -- analysis, and removed afterwards. If the equality operator comes
7406 -- from an explicit declaration, attach the inequality immediately
7407 -- after. Else the equality is inherited from a derived type
7408 -- declaration, so insert inequality after that declaration.
7410 if No (Alias (S)) then
7411 Insert_After (Unit_Declaration_Node (S), Decl);
7412 elsif Is_List_Member (Parent (S)) then
7413 Insert_After (Parent (S), Decl);
7415 Insert_After (Parent (Etype (First_Formal (S))), Decl);
7418 Mark_Rewrite_Insertion (Decl);
7419 Set_Is_Intrinsic_Subprogram (Op_Name);
7422 Set_Has_Completion (Op_Name);
7423 Set_Corresponding_Equality (Op_Name, S);
7424 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
7426 end Make_Inequality_Operator;
7428 ----------------------
7429 -- May_Need_Actuals --
7430 ----------------------
7432 procedure May_Need_Actuals (Fun : Entity_Id) is
7437 F := First_Formal (Fun);
7439 while Present (F) loop
7440 if No (Default_Value (F)) then
7448 Set_Needs_No_Actuals (Fun, B);
7449 end May_Need_Actuals;
7451 ---------------------
7452 -- Mode_Conformant --
7453 ---------------------
7455 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
7458 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
7460 end Mode_Conformant;
7462 ---------------------------
7463 -- New_Overloaded_Entity --
7464 ---------------------------
7466 procedure New_Overloaded_Entity
7468 Derived_Type : Entity_Id := Empty)
7470 Overridden_Subp : Entity_Id := Empty;
7471 -- Set if the current scope has an operation that is type-conformant
7472 -- with S, and becomes hidden by S.
7474 Is_Primitive_Subp : Boolean;
7475 -- Set to True if the new subprogram is primitive
7478 -- Entity that S overrides
7480 Prev_Vis : Entity_Id := Empty;
7481 -- Predecessor of E in Homonym chain
7483 procedure Check_For_Primitive_Subprogram
7484 (Is_Primitive : out Boolean;
7485 Is_Overriding : Boolean := False);
7486 -- If the subprogram being analyzed is a primitive operation of the type
7487 -- of a formal or result, set the Has_Primitive_Operations flag on the
7488 -- type, and set Is_Primitive to True (otherwise set to False). Set the
7489 -- corresponding flag on the entity itself for later use.
7491 procedure Check_Synchronized_Overriding
7492 (Def_Id : Entity_Id;
7493 Overridden_Subp : out Entity_Id);
7494 -- First determine if Def_Id is an entry or a subprogram either defined
7495 -- in the scope of a task or protected type, or is a primitive of such
7496 -- a type. Check whether Def_Id overrides a subprogram of an interface
7497 -- implemented by the synchronized type, return the overridden entity
7500 function Is_Private_Declaration (E : Entity_Id) return Boolean;
7501 -- Check that E is declared in the private part of the current package,
7502 -- or in the package body, where it may hide a previous declaration.
7503 -- We can't use In_Private_Part by itself because this flag is also
7504 -- set when freezing entities, so we must examine the place of the
7505 -- declaration in the tree, and recognize wrapper packages as well.
7507 function Is_Overriding_Alias
7509 New_E : Entity_Id) return Boolean;
7510 -- Check whether new subprogram and old subprogram are both inherited
7511 -- from subprograms that have distinct dispatch table entries. This can
7512 -- occur with derivations from instances with accidental homonyms.
7513 -- The function is conservative given that the converse is only true
7514 -- within instances that contain accidental overloadings.
7516 ------------------------------------
7517 -- Check_For_Primitive_Subprogram --
7518 ------------------------------------
7520 procedure Check_For_Primitive_Subprogram
7521 (Is_Primitive : out Boolean;
7522 Is_Overriding : Boolean := False)
7528 function Visible_Part_Type (T : Entity_Id) return Boolean;
7529 -- Returns true if T is declared in the visible part of the current
7530 -- package scope; otherwise returns false. Assumes that T is declared
7533 procedure Check_Private_Overriding (T : Entity_Id);
7534 -- Checks that if a primitive abstract subprogram of a visible
7535 -- abstract type is declared in a private part, then it must override
7536 -- an abstract subprogram declared in the visible part. Also checks
7537 -- that if a primitive function with a controlling result is declared
7538 -- in a private part, then it must override a function declared in
7539 -- the visible part.
7541 ------------------------------
7542 -- Check_Private_Overriding --
7543 ------------------------------
7545 procedure Check_Private_Overriding (T : Entity_Id) is
7547 if Is_Package_Or_Generic_Package (Current_Scope)
7548 and then In_Private_Part (Current_Scope)
7549 and then Visible_Part_Type (T)
7550 and then not In_Instance
7552 if Is_Abstract_Type (T)
7553 and then Is_Abstract_Subprogram (S)
7554 and then (not Is_Overriding
7555 or else not Is_Abstract_Subprogram (E))
7558 ("abstract subprograms must be visible "
7559 & "(RM 3.9.3(10))!", S);
7561 elsif Ekind (S) = E_Function
7562 and then not Is_Overriding
7564 if Is_Tagged_Type (T)
7565 and then T = Base_Type (Etype (S))
7568 ("private function with tagged result must"
7569 & " override visible-part function", S);
7571 ("\move subprogram to the visible part"
7572 & " (RM 3.9.3(10))", S);
7574 -- AI05-0073: extend this test to the case of a function
7575 -- with a controlling access result.
7577 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
7578 and then Is_Tagged_Type (Designated_Type (Etype (S)))
7580 not Is_Class_Wide_Type (Designated_Type (Etype (S)))
7581 and then Ada_Version >= Ada_2012
7584 ("private function with controlling access result "
7585 & "must override visible-part function", S);
7587 ("\move subprogram to the visible part"
7588 & " (RM 3.9.3(10))", S);
7592 end Check_Private_Overriding;
7594 -----------------------
7595 -- Visible_Part_Type --
7596 -----------------------
7598 function Visible_Part_Type (T : Entity_Id) return Boolean is
7599 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
7603 -- If the entity is a private type, then it must be declared in a
7606 if Ekind (T) in Private_Kind then
7610 -- Otherwise, we traverse the visible part looking for its
7611 -- corresponding declaration. We cannot use the declaration
7612 -- node directly because in the private part the entity of a
7613 -- private type is the one in the full view, which does not
7614 -- indicate that it is the completion of something visible.
7616 N := First (Visible_Declarations (Specification (P)));
7617 while Present (N) loop
7618 if Nkind (N) = N_Full_Type_Declaration
7619 and then Present (Defining_Identifier (N))
7620 and then T = Defining_Identifier (N)
7624 elsif Nkind_In (N, N_Private_Type_Declaration,
7625 N_Private_Extension_Declaration)
7626 and then Present (Defining_Identifier (N))
7627 and then T = Full_View (Defining_Identifier (N))
7636 end Visible_Part_Type;
7638 -- Start of processing for Check_For_Primitive_Subprogram
7641 Is_Primitive := False;
7643 if not Comes_From_Source (S) then
7646 -- If subprogram is at library level, it is not primitive operation
7648 elsif Current_Scope = Standard_Standard then
7651 elsif (Is_Package_Or_Generic_Package (Current_Scope)
7652 and then not In_Package_Body (Current_Scope))
7653 or else Is_Overriding
7655 -- For function, check return type
7657 if Ekind (S) = E_Function then
7658 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
7659 F_Typ := Designated_Type (Etype (S));
7664 B_Typ := Base_Type (F_Typ);
7666 if Scope (B_Typ) = Current_Scope
7667 and then not Is_Class_Wide_Type (B_Typ)
7668 and then not Is_Generic_Type (B_Typ)
7670 Is_Primitive := True;
7671 Set_Has_Primitive_Operations (B_Typ);
7672 Set_Is_Primitive (S);
7673 Check_Private_Overriding (B_Typ);
7677 -- For all subprograms, check formals
7679 Formal := First_Formal (S);
7680 while Present (Formal) loop
7681 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
7682 F_Typ := Designated_Type (Etype (Formal));
7684 F_Typ := Etype (Formal);
7687 B_Typ := Base_Type (F_Typ);
7689 if Ekind (B_Typ) = E_Access_Subtype then
7690 B_Typ := Base_Type (B_Typ);
7693 if Scope (B_Typ) = Current_Scope
7694 and then not Is_Class_Wide_Type (B_Typ)
7695 and then not Is_Generic_Type (B_Typ)
7697 Is_Primitive := True;
7698 Set_Is_Primitive (S);
7699 Set_Has_Primitive_Operations (B_Typ);
7700 Check_Private_Overriding (B_Typ);
7703 Next_Formal (Formal);
7706 end Check_For_Primitive_Subprogram;
7708 -----------------------------------
7709 -- Check_Synchronized_Overriding --
7710 -----------------------------------
7712 procedure Check_Synchronized_Overriding
7713 (Def_Id : Entity_Id;
7714 Overridden_Subp : out Entity_Id)
7716 Ifaces_List : Elist_Id;
7720 function Matches_Prefixed_View_Profile
7721 (Prim_Params : List_Id;
7722 Iface_Params : List_Id) return Boolean;
7723 -- Determine whether a subprogram's parameter profile Prim_Params
7724 -- matches that of a potentially overridden interface subprogram
7725 -- Iface_Params. Also determine if the type of first parameter of
7726 -- Iface_Params is an implemented interface.
7728 -----------------------------------
7729 -- Matches_Prefixed_View_Profile --
7730 -----------------------------------
7732 function Matches_Prefixed_View_Profile
7733 (Prim_Params : List_Id;
7734 Iface_Params : List_Id) return Boolean
7736 Iface_Id : Entity_Id;
7737 Iface_Param : Node_Id;
7738 Iface_Typ : Entity_Id;
7739 Prim_Id : Entity_Id;
7740 Prim_Param : Node_Id;
7741 Prim_Typ : Entity_Id;
7743 function Is_Implemented
7744 (Ifaces_List : Elist_Id;
7745 Iface : Entity_Id) return Boolean;
7746 -- Determine if Iface is implemented by the current task or
7749 --------------------
7750 -- Is_Implemented --
7751 --------------------
7753 function Is_Implemented
7754 (Ifaces_List : Elist_Id;
7755 Iface : Entity_Id) return Boolean
7757 Iface_Elmt : Elmt_Id;
7760 Iface_Elmt := First_Elmt (Ifaces_List);
7761 while Present (Iface_Elmt) loop
7762 if Node (Iface_Elmt) = Iface then
7766 Next_Elmt (Iface_Elmt);
7772 -- Start of processing for Matches_Prefixed_View_Profile
7775 Iface_Param := First (Iface_Params);
7776 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
7778 if Is_Access_Type (Iface_Typ) then
7779 Iface_Typ := Designated_Type (Iface_Typ);
7782 Prim_Param := First (Prim_Params);
7784 -- The first parameter of the potentially overridden subprogram
7785 -- must be an interface implemented by Prim.
7787 if not Is_Interface (Iface_Typ)
7788 or else not Is_Implemented (Ifaces_List, Iface_Typ)
7793 -- The checks on the object parameters are done, move onto the
7794 -- rest of the parameters.
7796 if not In_Scope then
7797 Prim_Param := Next (Prim_Param);
7800 Iface_Param := Next (Iface_Param);
7801 while Present (Iface_Param) and then Present (Prim_Param) loop
7802 Iface_Id := Defining_Identifier (Iface_Param);
7803 Iface_Typ := Find_Parameter_Type (Iface_Param);
7805 Prim_Id := Defining_Identifier (Prim_Param);
7806 Prim_Typ := Find_Parameter_Type (Prim_Param);
7808 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
7809 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
7810 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
7812 Iface_Typ := Designated_Type (Iface_Typ);
7813 Prim_Typ := Designated_Type (Prim_Typ);
7816 -- Case of multiple interface types inside a parameter profile
7818 -- (Obj_Param : in out Iface; ...; Param : Iface)
7820 -- If the interface type is implemented, then the matching type
7821 -- in the primitive should be the implementing record type.
7823 if Ekind (Iface_Typ) = E_Record_Type
7824 and then Is_Interface (Iface_Typ)
7825 and then Is_Implemented (Ifaces_List, Iface_Typ)
7827 if Prim_Typ /= Typ then
7831 -- The two parameters must be both mode and subtype conformant
7833 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
7835 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
7844 -- One of the two lists contains more parameters than the other
7846 if Present (Iface_Param) or else Present (Prim_Param) then
7851 end Matches_Prefixed_View_Profile;
7853 -- Start of processing for Check_Synchronized_Overriding
7856 Overridden_Subp := Empty;
7858 -- Def_Id must be an entry or a subprogram. We should skip predefined
7859 -- primitives internally generated by the frontend; however at this
7860 -- stage predefined primitives are still not fully decorated. As a
7861 -- minor optimization we skip here internally generated subprograms.
7863 if (Ekind (Def_Id) /= E_Entry
7864 and then Ekind (Def_Id) /= E_Function
7865 and then Ekind (Def_Id) /= E_Procedure)
7866 or else not Comes_From_Source (Def_Id)
7871 -- Search for the concurrent declaration since it contains the list
7872 -- of all implemented interfaces. In this case, the subprogram is
7873 -- declared within the scope of a protected or a task type.
7875 if Present (Scope (Def_Id))
7876 and then Is_Concurrent_Type (Scope (Def_Id))
7877 and then not Is_Generic_Actual_Type (Scope (Def_Id))
7879 Typ := Scope (Def_Id);
7882 -- The enclosing scope is not a synchronized type and the subprogram
7885 elsif No (First_Formal (Def_Id)) then
7888 -- The subprogram has formals and hence it may be a primitive of a
7892 Typ := Etype (First_Formal (Def_Id));
7894 if Is_Access_Type (Typ) then
7895 Typ := Directly_Designated_Type (Typ);
7898 if Is_Concurrent_Type (Typ)
7899 and then not Is_Generic_Actual_Type (Typ)
7903 -- This case occurs when the concurrent type is declared within
7904 -- a generic unit. As a result the corresponding record has been
7905 -- built and used as the type of the first formal, we just have
7906 -- to retrieve the corresponding concurrent type.
7908 elsif Is_Concurrent_Record_Type (Typ)
7909 and then Present (Corresponding_Concurrent_Type (Typ))
7911 Typ := Corresponding_Concurrent_Type (Typ);
7919 -- There is no overriding to check if is an inherited operation in a
7920 -- type derivation on for a generic actual.
7922 Collect_Interfaces (Typ, Ifaces_List);
7924 if Is_Empty_Elmt_List (Ifaces_List) then
7928 -- Determine whether entry or subprogram Def_Id overrides a primitive
7929 -- operation that belongs to one of the interfaces in Ifaces_List.
7932 Candidate : Entity_Id := Empty;
7933 Hom : Entity_Id := Empty;
7934 Iface_Typ : Entity_Id;
7935 Subp : Entity_Id := Empty;
7938 -- Traverse the homonym chain, looking for a potentially
7939 -- overridden subprogram that belongs to an implemented
7942 Hom := Current_Entity_In_Scope (Def_Id);
7943 while Present (Hom) loop
7947 or else not Is_Overloadable (Subp)
7948 or else not Is_Primitive (Subp)
7949 or else not Is_Dispatching_Operation (Subp)
7950 or else not Present (Find_Dispatching_Type (Subp))
7951 or else not Is_Interface (Find_Dispatching_Type (Subp))
7955 -- Entries and procedures can override abstract or null
7956 -- interface procedures.
7958 elsif (Ekind (Def_Id) = E_Procedure
7959 or else Ekind (Def_Id) = E_Entry)
7960 and then Ekind (Subp) = E_Procedure
7961 and then Matches_Prefixed_View_Profile
7962 (Parameter_Specifications (Parent (Def_Id)),
7963 Parameter_Specifications (Parent (Subp)))
7967 -- For an overridden subprogram Subp, check whether the mode
7968 -- of its first parameter is correct depending on the kind
7969 -- of synchronized type.
7972 Formal : constant Node_Id := First_Formal (Candidate);
7975 -- In order for an entry or a protected procedure to
7976 -- override, the first parameter of the overridden
7977 -- routine must be of mode "out", "in out" or
7978 -- access-to-variable.
7980 if (Ekind (Candidate) = E_Entry
7981 or else Ekind (Candidate) = E_Procedure)
7982 and then Is_Protected_Type (Typ)
7983 and then Ekind (Formal) /= E_In_Out_Parameter
7984 and then Ekind (Formal) /= E_Out_Parameter
7985 and then Nkind (Parameter_Type (Parent (Formal)))
7986 /= N_Access_Definition
7990 -- All other cases are OK since a task entry or routine
7991 -- does not have a restriction on the mode of the first
7992 -- parameter of the overridden interface routine.
7995 Overridden_Subp := Candidate;
8000 -- Functions can override abstract interface functions
8002 elsif Ekind (Def_Id) = E_Function
8003 and then Ekind (Subp) = E_Function
8004 and then Matches_Prefixed_View_Profile
8005 (Parameter_Specifications (Parent (Def_Id)),
8006 Parameter_Specifications (Parent (Subp)))
8007 and then Etype (Result_Definition (Parent (Def_Id))) =
8008 Etype (Result_Definition (Parent (Subp)))
8010 Overridden_Subp := Subp;
8014 Hom := Homonym (Hom);
8017 -- After examining all candidates for overriding, we are left with
8018 -- the best match which is a mode incompatible interface routine.
8019 -- Do not emit an error if the Expander is active since this error
8020 -- will be detected later on after all concurrent types are
8021 -- expanded and all wrappers are built. This check is meant for
8022 -- spec-only compilations.
8024 if Present (Candidate) and then not Expander_Active then
8026 Find_Parameter_Type (Parent (First_Formal (Candidate)));
8028 -- Def_Id is primitive of a protected type, declared inside the
8029 -- type, and the candidate is primitive of a limited or
8030 -- synchronized interface.
8033 and then Is_Protected_Type (Typ)
8035 (Is_Limited_Interface (Iface_Typ)
8036 or else Is_Protected_Interface (Iface_Typ)
8037 or else Is_Synchronized_Interface (Iface_Typ)
8038 or else Is_Task_Interface (Iface_Typ))
8041 ("first formal of & must be of mode `OUT`, `IN OUT`"
8042 & " or access-to-variable", Typ, Candidate);
8044 ("\in order to be overridden by protected procedure or "
8045 & "entry (RM 9.4(11.9/2))", Typ);
8049 Overridden_Subp := Candidate;
8052 end Check_Synchronized_Overriding;
8054 ----------------------------
8055 -- Is_Private_Declaration --
8056 ----------------------------
8058 function Is_Private_Declaration (E : Entity_Id) return Boolean is
8059 Priv_Decls : List_Id;
8060 Decl : constant Node_Id := Unit_Declaration_Node (E);
8063 if Is_Package_Or_Generic_Package (Current_Scope)
8064 and then In_Private_Part (Current_Scope)
8067 Private_Declarations (
8068 Specification (Unit_Declaration_Node (Current_Scope)));
8070 return In_Package_Body (Current_Scope)
8072 (Is_List_Member (Decl)
8073 and then List_Containing (Decl) = Priv_Decls)
8074 or else (Nkind (Parent (Decl)) = N_Package_Specification
8077 (Defining_Entity (Parent (Decl)))
8078 and then List_Containing (Parent (Parent (Decl)))
8083 end Is_Private_Declaration;
8085 --------------------------
8086 -- Is_Overriding_Alias --
8087 --------------------------
8089 function Is_Overriding_Alias
8091 New_E : Entity_Id) return Boolean
8093 AO : constant Entity_Id := Alias (Old_E);
8094 AN : constant Entity_Id := Alias (New_E);
8097 return Scope (AO) /= Scope (AN)
8098 or else No (DTC_Entity (AO))
8099 or else No (DTC_Entity (AN))
8100 or else DT_Position (AO) = DT_Position (AN);
8101 end Is_Overriding_Alias;
8103 -- Start of processing for New_Overloaded_Entity
8106 -- We need to look for an entity that S may override. This must be a
8107 -- homonym in the current scope, so we look for the first homonym of
8108 -- S in the current scope as the starting point for the search.
8110 E := Current_Entity_In_Scope (S);
8112 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
8113 -- They are directly added to the list of primitive operations of
8114 -- Derived_Type, unless this is a rederivation in the private part
8115 -- of an operation that was already derived in the visible part of
8116 -- the current package.
8118 if Ada_Version >= Ada_2005
8119 and then Present (Derived_Type)
8120 and then Present (Alias (S))
8121 and then Is_Dispatching_Operation (Alias (S))
8122 and then Present (Find_Dispatching_Type (Alias (S)))
8123 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
8125 -- For private types, when the full-view is processed we propagate to
8126 -- the full view the non-overridden entities whose attribute "alias"
8127 -- references an interface primitive. These entities were added by
8128 -- Derive_Subprograms to ensure that interface primitives are
8131 -- Inside_Freeze_Actions is non zero when S corresponds with an
8132 -- internal entity that links an interface primitive with its
8133 -- covering primitive through attribute Interface_Alias (see
8134 -- Add_Internal_Interface_Entities).
8136 if Inside_Freezing_Actions = 0
8137 and then Is_Package_Or_Generic_Package (Current_Scope)
8138 and then In_Private_Part (Current_Scope)
8139 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
8140 and then Nkind (Parent (S)) = N_Full_Type_Declaration
8141 and then Full_View (Defining_Identifier (Parent (E)))
8142 = Defining_Identifier (Parent (S))
8143 and then Alias (E) = Alias (S)
8145 Check_Operation_From_Private_View (S, E);
8146 Set_Is_Dispatching_Operation (S);
8151 Enter_Overloaded_Entity (S);
8152 Check_Dispatching_Operation (S, Empty);
8153 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
8159 -- If there is no homonym then this is definitely not overriding
8162 Enter_Overloaded_Entity (S);
8163 Check_Dispatching_Operation (S, Empty);
8164 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
8166 -- If subprogram has an explicit declaration, check whether it
8167 -- has an overriding indicator.
8169 if Comes_From_Source (S) then
8170 Check_Synchronized_Overriding (S, Overridden_Subp);
8172 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
8173 -- it may have overridden some hidden inherited primitive. Update
8174 -- Overridden_Subp to avoid spurious errors when checking the
8175 -- overriding indicator.
8177 if Ada_Version >= Ada_2012
8178 and then No (Overridden_Subp)
8179 and then Is_Dispatching_Operation (S)
8180 and then Present (Overridden_Operation (S))
8182 Overridden_Subp := Overridden_Operation (S);
8185 Check_Overriding_Indicator
8186 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
8189 -- If there is a homonym that is not overloadable, then we have an
8190 -- error, except for the special cases checked explicitly below.
8192 elsif not Is_Overloadable (E) then
8194 -- Check for spurious conflict produced by a subprogram that has the
8195 -- same name as that of the enclosing generic package. The conflict
8196 -- occurs within an instance, between the subprogram and the renaming
8197 -- declaration for the package. After the subprogram, the package
8198 -- renaming declaration becomes hidden.
8200 if Ekind (E) = E_Package
8201 and then Present (Renamed_Object (E))
8202 and then Renamed_Object (E) = Current_Scope
8203 and then Nkind (Parent (Renamed_Object (E))) =
8204 N_Package_Specification
8205 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
8208 Set_Is_Immediately_Visible (E, False);
8209 Enter_Overloaded_Entity (S);
8210 Set_Homonym (S, Homonym (E));
8211 Check_Dispatching_Operation (S, Empty);
8212 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
8214 -- If the subprogram is implicit it is hidden by the previous
8215 -- declaration. However if it is dispatching, it must appear in the
8216 -- dispatch table anyway, because it can be dispatched to even if it
8217 -- cannot be called directly.
8219 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
8220 Set_Scope (S, Current_Scope);
8222 if Is_Dispatching_Operation (Alias (S)) then
8223 Check_Dispatching_Operation (S, Empty);
8229 Error_Msg_Sloc := Sloc (E);
8231 -- Generate message, with useful additional warning if in generic
8233 if Is_Generic_Unit (E) then
8234 Error_Msg_N ("previous generic unit cannot be overloaded", S);
8235 Error_Msg_N ("\& conflicts with declaration#", S);
8237 Error_Msg_N ("& conflicts with declaration#", S);
8243 -- E exists and is overloadable
8246 Check_Synchronized_Overriding (S, Overridden_Subp);
8248 -- Loop through E and its homonyms to determine if any of them is
8249 -- the candidate for overriding by S.
8251 while Present (E) loop
8253 -- Definitely not interesting if not in the current scope
8255 if Scope (E) /= Current_Scope then
8258 -- Check if we have type conformance
8260 elsif Type_Conformant (E, S) then
8262 -- If the old and new entities have the same profile and one
8263 -- is not the body of the other, then this is an error, unless
8264 -- one of them is implicitly declared.
8266 -- There are some cases when both can be implicit, for example
8267 -- when both a literal and a function that overrides it are
8268 -- inherited in a derivation, or when an inherited operation
8269 -- of a tagged full type overrides the inherited operation of
8270 -- a private extension. Ada 83 had a special rule for the
8271 -- literal case. In Ada95, the later implicit operation hides
8272 -- the former, and the literal is always the former. In the
8273 -- odd case where both are derived operations declared at the
8274 -- same point, both operations should be declared, and in that
8275 -- case we bypass the following test and proceed to the next
8276 -- part. This can only occur for certain obscure cases in
8277 -- instances, when an operation on a type derived from a formal
8278 -- private type does not override a homograph inherited from
8279 -- the actual. In subsequent derivations of such a type, the
8280 -- DT positions of these operations remain distinct, if they
8283 if Present (Alias (S))
8284 and then (No (Alias (E))
8285 or else Comes_From_Source (E)
8286 or else Is_Abstract_Subprogram (S)
8288 (Is_Dispatching_Operation (E)
8289 and then Is_Overriding_Alias (E, S)))
8290 and then Ekind (E) /= E_Enumeration_Literal
8292 -- When an derived operation is overloaded it may be due to
8293 -- the fact that the full view of a private extension
8294 -- re-inherits. It has to be dealt with.
8296 if Is_Package_Or_Generic_Package (Current_Scope)
8297 and then In_Private_Part (Current_Scope)
8299 Check_Operation_From_Private_View (S, E);
8302 -- In any case the implicit operation remains hidden by the
8303 -- existing declaration, which is overriding. Indicate that
8304 -- E overrides the operation from which S is inherited.
8306 if Present (Alias (S)) then
8307 Set_Overridden_Operation (E, Alias (S));
8309 Set_Overridden_Operation (E, S);
8312 if Comes_From_Source (E) then
8313 Check_Overriding_Indicator (E, S, Is_Primitive => False);
8318 -- Within an instance, the renaming declarations for actual
8319 -- subprograms may become ambiguous, but they do not hide each
8322 elsif Ekind (E) /= E_Entry
8323 and then not Comes_From_Source (E)
8324 and then not Is_Generic_Instance (E)
8325 and then (Present (Alias (E))
8326 or else Is_Intrinsic_Subprogram (E))
8327 and then (not In_Instance
8328 or else No (Parent (E))
8329 or else Nkind (Unit_Declaration_Node (E)) /=
8330 N_Subprogram_Renaming_Declaration)
8332 -- A subprogram child unit is not allowed to override an
8333 -- inherited subprogram (10.1.1(20)).
8335 if Is_Child_Unit (S) then
8337 ("child unit overrides inherited subprogram in parent",
8342 if Is_Non_Overriding_Operation (E, S) then
8343 Enter_Overloaded_Entity (S);
8345 if No (Derived_Type)
8346 or else Is_Tagged_Type (Derived_Type)
8348 Check_Dispatching_Operation (S, Empty);
8354 -- E is a derived operation or an internal operator which
8355 -- is being overridden. Remove E from further visibility.
8356 -- Furthermore, if E is a dispatching operation, it must be
8357 -- replaced in the list of primitive operations of its type
8358 -- (see Override_Dispatching_Operation).
8360 Overridden_Subp := E;
8366 Prev := First_Entity (Current_Scope);
8367 while Present (Prev)
8368 and then Next_Entity (Prev) /= E
8373 -- It is possible for E to be in the current scope and
8374 -- yet not in the entity chain. This can only occur in a
8375 -- generic context where E is an implicit concatenation
8376 -- in the formal part, because in a generic body the
8377 -- entity chain starts with the formals.
8380 (Present (Prev) or else Chars (E) = Name_Op_Concat);
8382 -- E must be removed both from the entity_list of the
8383 -- current scope, and from the visibility chain
8385 if Debug_Flag_E then
8386 Write_Str ("Override implicit operation ");
8387 Write_Int (Int (E));
8391 -- If E is a predefined concatenation, it stands for four
8392 -- different operations. As a result, a single explicit
8393 -- declaration does not hide it. In a possible ambiguous
8394 -- situation, Disambiguate chooses the user-defined op,
8395 -- so it is correct to retain the previous internal one.
8397 if Chars (E) /= Name_Op_Concat
8398 or else Ekind (E) /= E_Operator
8400 -- For nondispatching derived operations that are
8401 -- overridden by a subprogram declared in the private
8402 -- part of a package, we retain the derived subprogram
8403 -- but mark it as not immediately visible. If the
8404 -- derived operation was declared in the visible part
8405 -- then this ensures that it will still be visible
8406 -- outside the package with the proper signature
8407 -- (calls from outside must also be directed to this
8408 -- version rather than the overriding one, unlike the
8409 -- dispatching case). Calls from inside the package
8410 -- will still resolve to the overriding subprogram
8411 -- since the derived one is marked as not visible
8412 -- within the package.
8414 -- If the private operation is dispatching, we achieve
8415 -- the overriding by keeping the implicit operation
8416 -- but setting its alias to be the overriding one. In
8417 -- this fashion the proper body is executed in all
8418 -- cases, but the original signature is used outside
8421 -- If the overriding is not in the private part, we
8422 -- remove the implicit operation altogether.
8424 if Is_Private_Declaration (S) then
8425 if not Is_Dispatching_Operation (E) then
8426 Set_Is_Immediately_Visible (E, False);
8428 -- Work done in Override_Dispatching_Operation,
8429 -- so nothing else need to be done here.
8435 -- Find predecessor of E in Homonym chain
8437 if E = Current_Entity (E) then
8440 Prev_Vis := Current_Entity (E);
8441 while Homonym (Prev_Vis) /= E loop
8442 Prev_Vis := Homonym (Prev_Vis);
8446 if Prev_Vis /= Empty then
8448 -- Skip E in the visibility chain
8450 Set_Homonym (Prev_Vis, Homonym (E));
8453 Set_Name_Entity_Id (Chars (E), Homonym (E));
8456 Set_Next_Entity (Prev, Next_Entity (E));
8458 if No (Next_Entity (Prev)) then
8459 Set_Last_Entity (Current_Scope, Prev);
8464 Enter_Overloaded_Entity (S);
8466 -- For entities generated by Derive_Subprograms the
8467 -- overridden operation is the inherited primitive
8468 -- (which is available through the attribute alias).
8470 if not (Comes_From_Source (E))
8471 and then Is_Dispatching_Operation (E)
8472 and then Find_Dispatching_Type (E) =
8473 Find_Dispatching_Type (S)
8474 and then Present (Alias (E))
8475 and then Comes_From_Source (Alias (E))
8477 Set_Overridden_Operation (S, Alias (E));
8479 -- Normal case of setting entity as overridden
8481 -- Note: Static_Initialization and Overridden_Operation
8482 -- attributes use the same field in subprogram entities.
8483 -- Static_Initialization is only defined for internal
8484 -- initialization procedures, where Overridden_Operation
8485 -- is irrelevant. Therefore the setting of this attribute
8486 -- must check whether the target is an init_proc.
8488 elsif not Is_Init_Proc (S) then
8489 Set_Overridden_Operation (S, E);
8492 Check_Overriding_Indicator (S, E, Is_Primitive => True);
8494 -- If S is a user-defined subprogram or a null procedure
8495 -- expanded to override an inherited null procedure, or a
8496 -- predefined dispatching primitive then indicate that E
8497 -- overrides the operation from which S is inherited.
8499 if Comes_From_Source (S)
8501 (Present (Parent (S))
8503 Nkind (Parent (S)) = N_Procedure_Specification
8505 Null_Present (Parent (S)))
8507 (Present (Alias (E))
8509 Is_Predefined_Dispatching_Operation (Alias (E)))
8511 if Present (Alias (E)) then
8512 Set_Overridden_Operation (S, Alias (E));
8516 if Is_Dispatching_Operation (E) then
8518 -- An overriding dispatching subprogram inherits the
8519 -- convention of the overridden subprogram (AI-117).
8521 Set_Convention (S, Convention (E));
8522 Check_Dispatching_Operation (S, E);
8525 Check_Dispatching_Operation (S, Empty);
8528 Check_For_Primitive_Subprogram
8529 (Is_Primitive_Subp, Is_Overriding => True);
8530 goto Check_Inequality;
8533 -- Apparent redeclarations in instances can occur when two
8534 -- formal types get the same actual type. The subprograms in
8535 -- in the instance are legal, even if not callable from the
8536 -- outside. Calls from within are disambiguated elsewhere.
8537 -- For dispatching operations in the visible part, the usual
8538 -- rules apply, and operations with the same profile are not
8541 elsif (In_Instance_Visible_Part
8542 and then not Is_Dispatching_Operation (E))
8543 or else In_Instance_Not_Visible
8547 -- Here we have a real error (identical profile)
8550 Error_Msg_Sloc := Sloc (E);
8552 -- Avoid cascaded errors if the entity appears in
8553 -- subsequent calls.
8555 Set_Scope (S, Current_Scope);
8557 -- Generate error, with extra useful warning for the case
8558 -- of a generic instance with no completion.
8560 if Is_Generic_Instance (S)
8561 and then not Has_Completion (E)
8564 ("instantiation cannot provide body for&", S);
8565 Error_Msg_N ("\& conflicts with declaration#", S);
8567 Error_Msg_N ("& conflicts with declaration#", S);
8574 -- If one subprogram has an access parameter and the other
8575 -- a parameter of an access type, calls to either might be
8576 -- ambiguous. Verify that parameters match except for the
8577 -- access parameter.
8579 if May_Hide_Profile then
8585 F1 := First_Formal (S);
8586 F2 := First_Formal (E);
8587 while Present (F1) and then Present (F2) loop
8588 if Is_Access_Type (Etype (F1)) then
8589 if not Is_Access_Type (Etype (F2))
8590 or else not Conforming_Types
8591 (Designated_Type (Etype (F1)),
8592 Designated_Type (Etype (F2)),
8595 May_Hide_Profile := False;
8599 not Conforming_Types
8600 (Etype (F1), Etype (F2), Type_Conformant)
8602 May_Hide_Profile := False;
8613 Error_Msg_NE ("calls to& may be ambiguous?", S, S);
8622 -- On exit, we know that S is a new entity
8624 Enter_Overloaded_Entity (S);
8625 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
8626 Check_Overriding_Indicator
8627 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
8629 -- Overloading is not allowed in SPARK, except for operators
8631 if Nkind (S) /= N_Defining_Operator_Symbol then
8632 Error_Msg_Sloc := Sloc (Homonym (S));
8633 Check_SPARK_Restriction
8634 ("overloading not allowed with entity#", S);
8637 -- If S is a derived operation for an untagged type then by
8638 -- definition it's not a dispatching operation (even if the parent
8639 -- operation was dispatching), so Check_Dispatching_Operation is not
8640 -- called in that case.
8642 if No (Derived_Type)
8643 or else Is_Tagged_Type (Derived_Type)
8645 Check_Dispatching_Operation (S, Empty);
8649 -- If this is a user-defined equality operator that is not a derived
8650 -- subprogram, create the corresponding inequality. If the operation is
8651 -- dispatching, the expansion is done elsewhere, and we do not create
8652 -- an explicit inequality operation.
8654 <<Check_Inequality>>
8655 if Chars (S) = Name_Op_Eq
8656 and then Etype (S) = Standard_Boolean
8657 and then Present (Parent (S))
8658 and then not Is_Dispatching_Operation (S)
8660 Make_Inequality_Operator (S);
8662 if Ada_Version >= Ada_2012 then
8663 Check_Untagged_Equality (S);
8666 end New_Overloaded_Entity;
8668 ---------------------
8669 -- Process_Formals --
8670 ---------------------
8672 procedure Process_Formals
8674 Related_Nod : Node_Id)
8676 Param_Spec : Node_Id;
8678 Formal_Type : Entity_Id;
8682 Num_Out_Params : Nat := 0;
8683 First_Out_Param : Entity_Id := Empty;
8684 -- Used for setting Is_Only_Out_Parameter
8686 function Designates_From_With_Type (Typ : Entity_Id) return Boolean;
8687 -- Determine whether an access type designates a type coming from a
8690 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
8691 -- Check whether the default has a class-wide type. After analysis the
8692 -- default has the type of the formal, so we must also check explicitly
8693 -- for an access attribute.
8695 -------------------------------
8696 -- Designates_From_With_Type --
8697 -------------------------------
8699 function Designates_From_With_Type (Typ : Entity_Id) return Boolean is
8700 Desig : Entity_Id := Typ;
8703 if Is_Access_Type (Desig) then
8704 Desig := Directly_Designated_Type (Desig);
8707 if Is_Class_Wide_Type (Desig) then
8708 Desig := Root_Type (Desig);
8712 Ekind (Desig) = E_Incomplete_Type
8713 and then From_With_Type (Desig);
8714 end Designates_From_With_Type;
8716 ---------------------------
8717 -- Is_Class_Wide_Default --
8718 ---------------------------
8720 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
8722 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
8723 or else (Nkind (D) = N_Attribute_Reference
8724 and then Attribute_Name (D) = Name_Access
8725 and then Is_Class_Wide_Type (Etype (Prefix (D))));
8726 end Is_Class_Wide_Default;
8728 -- Start of processing for Process_Formals
8731 -- In order to prevent premature use of the formals in the same formal
8732 -- part, the Ekind is left undefined until all default expressions are
8733 -- analyzed. The Ekind is established in a separate loop at the end.
8735 Param_Spec := First (T);
8736 while Present (Param_Spec) loop
8737 Formal := Defining_Identifier (Param_Spec);
8738 Set_Never_Set_In_Source (Formal, True);
8739 Enter_Name (Formal);
8741 -- Case of ordinary parameters
8743 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
8744 Find_Type (Parameter_Type (Param_Spec));
8745 Ptype := Parameter_Type (Param_Spec);
8747 if Ptype = Error then
8751 Formal_Type := Entity (Ptype);
8753 if Is_Incomplete_Type (Formal_Type)
8755 (Is_Class_Wide_Type (Formal_Type)
8756 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
8758 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
8759 -- primitive operations, as long as their completion is
8760 -- in the same declarative part. If in the private part
8761 -- this means that the type cannot be a Taft-amendment type.
8762 -- Check is done on package exit. For access to subprograms,
8763 -- the use is legal for Taft-amendment types.
8765 if Is_Tagged_Type (Formal_Type) then
8766 if Ekind (Scope (Current_Scope)) = E_Package
8767 and then not From_With_Type (Formal_Type)
8768 and then not Is_Class_Wide_Type (Formal_Type)
8771 (Parent (T), N_Access_Function_Definition,
8772 N_Access_Procedure_Definition)
8776 Private_Dependents (Base_Type (Formal_Type)));
8778 -- Freezing is delayed to ensure that Register_Prim
8779 -- will get called for this operation, which is needed
8780 -- in cases where static dispatch tables aren't built.
8781 -- (Note that the same is done for controlling access
8782 -- parameter cases in function Access_Definition.)
8784 Set_Has_Delayed_Freeze (Current_Scope);
8788 -- Special handling of Value_Type for CIL case
8790 elsif Is_Value_Type (Formal_Type) then
8793 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
8794 N_Access_Procedure_Definition)
8797 -- AI05-0151: Tagged incomplete types are allowed in all
8798 -- formal parts. Untagged incomplete types are not allowed
8801 if Ada_Version >= Ada_2012 then
8802 if Is_Tagged_Type (Formal_Type) then
8805 elsif Nkind_In (Parent (Parent (T)), N_Accept_Statement,
8810 ("invalid use of untagged incomplete type&",
8811 Ptype, Formal_Type);
8816 ("invalid use of incomplete type&",
8817 Param_Spec, Formal_Type);
8819 -- Further checks on the legality of incomplete types
8820 -- in formal parts are delayed until the freeze point
8821 -- of the enclosing subprogram or access to subprogram.
8825 elsif Ekind (Formal_Type) = E_Void then
8827 ("premature use of&",
8828 Parameter_Type (Param_Spec), Formal_Type);
8831 -- Ada 2005 (AI-231): Create and decorate an internal subtype
8832 -- declaration corresponding to the null-excluding type of the
8833 -- formal in the enclosing scope. Finally, replace the parameter
8834 -- type of the formal with the internal subtype.
8836 if Ada_Version >= Ada_2005
8837 and then Null_Exclusion_Present (Param_Spec)
8839 if not Is_Access_Type (Formal_Type) then
8841 ("`NOT NULL` allowed only for an access type", Param_Spec);
8844 if Can_Never_Be_Null (Formal_Type)
8845 and then Comes_From_Source (Related_Nod)
8848 ("`NOT NULL` not allowed (& already excludes null)",
8849 Param_Spec, Formal_Type);
8853 Create_Null_Excluding_Itype
8855 Related_Nod => Related_Nod,
8856 Scope_Id => Scope (Current_Scope));
8858 -- If the designated type of the itype is an itype we
8859 -- decorate it with the Has_Delayed_Freeze attribute to
8860 -- avoid problems with the backend.
8863 -- type T is access procedure;
8864 -- procedure Op (O : not null T);
8866 if Is_Itype (Directly_Designated_Type (Formal_Type)) then
8867 Set_Has_Delayed_Freeze (Formal_Type);
8872 -- An access formal type
8876 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
8878 -- No need to continue if we already notified errors
8880 if not Present (Formal_Type) then
8884 -- Ada 2005 (AI-254)
8887 AD : constant Node_Id :=
8888 Access_To_Subprogram_Definition
8889 (Parameter_Type (Param_Spec));
8891 if Present (AD) and then Protected_Present (AD) then
8893 Replace_Anonymous_Access_To_Protected_Subprogram
8899 Set_Etype (Formal, Formal_Type);
8901 Default := Expression (Param_Spec);
8903 if Present (Default) then
8904 Check_SPARK_Restriction
8905 ("default expression is not allowed", Default);
8907 if Out_Present (Param_Spec) then
8909 ("default initialization only allowed for IN parameters",
8913 -- Do the special preanalysis of the expression (see section on
8914 -- "Handling of Default Expressions" in the spec of package Sem).
8916 Preanalyze_Spec_Expression (Default, Formal_Type);
8918 -- An access to constant cannot be the default for
8919 -- an access parameter that is an access to variable.
8921 if Ekind (Formal_Type) = E_Anonymous_Access_Type
8922 and then not Is_Access_Constant (Formal_Type)
8923 and then Is_Access_Type (Etype (Default))
8924 and then Is_Access_Constant (Etype (Default))
8927 ("formal that is access to variable cannot be initialized " &
8928 "with an access-to-constant expression", Default);
8931 -- Check that the designated type of an access parameter's default
8932 -- is not a class-wide type unless the parameter's designated type
8933 -- is also class-wide.
8935 if Ekind (Formal_Type) = E_Anonymous_Access_Type
8936 and then not Designates_From_With_Type (Formal_Type)
8937 and then Is_Class_Wide_Default (Default)
8938 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
8941 ("access to class-wide expression not allowed here", Default);
8944 -- Check incorrect use of dynamically tagged expressions
8946 if Is_Tagged_Type (Formal_Type) then
8947 Check_Dynamically_Tagged_Expression
8950 Related_Nod => Default);
8954 -- Ada 2005 (AI-231): Static checks
8956 if Ada_Version >= Ada_2005
8957 and then Is_Access_Type (Etype (Formal))
8958 and then Can_Never_Be_Null (Etype (Formal))
8960 Null_Exclusion_Static_Checks (Param_Spec);
8967 -- If this is the formal part of a function specification, analyze the
8968 -- subtype mark in the context where the formals are visible but not
8969 -- yet usable, and may hide outer homographs.
8971 if Nkind (Related_Nod) = N_Function_Specification then
8972 Analyze_Return_Type (Related_Nod);
8975 -- Now set the kind (mode) of each formal
8977 Param_Spec := First (T);
8978 while Present (Param_Spec) loop
8979 Formal := Defining_Identifier (Param_Spec);
8980 Set_Formal_Mode (Formal);
8982 if Ekind (Formal) = E_In_Parameter then
8983 Set_Default_Value (Formal, Expression (Param_Spec));
8985 if Present (Expression (Param_Spec)) then
8986 Default := Expression (Param_Spec);
8988 if Is_Scalar_Type (Etype (Default)) then
8990 (Parameter_Type (Param_Spec)) /= N_Access_Definition
8992 Formal_Type := Entity (Parameter_Type (Param_Spec));
8995 Formal_Type := Access_Definition
8996 (Related_Nod, Parameter_Type (Param_Spec));
8999 Apply_Scalar_Range_Check (Default, Formal_Type);
9003 elsif Ekind (Formal) = E_Out_Parameter then
9004 Num_Out_Params := Num_Out_Params + 1;
9006 if Num_Out_Params = 1 then
9007 First_Out_Param := Formal;
9010 elsif Ekind (Formal) = E_In_Out_Parameter then
9011 Num_Out_Params := Num_Out_Params + 1;
9017 if Present (First_Out_Param) and then Num_Out_Params = 1 then
9018 Set_Is_Only_Out_Parameter (First_Out_Param);
9020 end Process_Formals;
9026 procedure Process_PPCs
9028 Spec_Id : Entity_Id;
9029 Body_Id : Entity_Id)
9031 Loc : constant Source_Ptr := Sloc (N);
9035 Designator : Entity_Id;
9036 -- Subprogram designator, set from Spec_Id if present, else Body_Id
9038 Precond : Node_Id := Empty;
9039 -- Set non-Empty if we prepend precondition to the declarations. This
9040 -- is used to hook up inherited preconditions (adding the condition
9041 -- expression with OR ELSE, and adding the message).
9043 Inherited_Precond : Node_Id;
9044 -- Precondition inherited from parent subprogram
9046 Inherited : constant Subprogram_List :=
9047 Inherited_Subprograms (Spec_Id);
9048 -- List of subprograms inherited by this subprogram
9050 Plist : List_Id := No_List;
9051 -- List of generated postconditions
9053 function Grab_PPC (Pspec : Entity_Id := Empty) return Node_Id;
9054 -- Prag contains an analyzed precondition or postcondition pragma. This
9055 -- function copies the pragma, changes it to the corresponding Check
9056 -- pragma and returns the Check pragma as the result. If Pspec is non-
9057 -- empty, this is the case of inheriting a PPC, where we must change
9058 -- references to parameters of the inherited subprogram to point to the
9059 -- corresponding parameters of the current subprogram.
9061 function Invariants_Or_Predicates_Present return Boolean;
9062 -- Determines if any invariants or predicates are present for any OUT
9063 -- or IN OUT parameters of the subprogram, or (for a function) if the
9064 -- return value has an invariant.
9070 function Grab_PPC (Pspec : Entity_Id := Empty) return Node_Id is
9071 Nam : constant Name_Id := Pragma_Name (Prag);
9076 -- Prepare map if this is the case where we have to map entities of
9077 -- arguments in the overridden subprogram to corresponding entities
9078 -- of the current subprogram.
9089 Map := New_Elmt_List;
9090 PF := First_Formal (Pspec);
9091 CF := First_Formal (Designator);
9092 while Present (PF) loop
9093 Append_Elmt (PF, Map);
9094 Append_Elmt (CF, Map);
9101 -- Now we can copy the tree, doing any required substitutions
9103 CP := New_Copy_Tree (Prag, Map => Map, New_Scope => Current_Scope);
9105 -- Set Analyzed to false, since we want to reanalyze the check
9106 -- procedure. Note that it is only at the outer level that we
9107 -- do this fiddling, for the spec cases, the already preanalyzed
9108 -- parameters are not affected.
9110 Set_Analyzed (CP, False);
9112 -- We also make sure Comes_From_Source is False for the copy
9114 Set_Comes_From_Source (CP, False);
9116 -- For a postcondition pragma within a generic, preserve the pragma
9117 -- for later expansion.
9119 if Nam = Name_Postcondition
9120 and then not Expander_Active
9125 -- Change copy of pragma into corresponding pragma Check
9127 Prepend_To (Pragma_Argument_Associations (CP),
9128 Make_Pragma_Argument_Association (Sloc (Prag),
9129 Expression => Make_Identifier (Loc, Nam)));
9130 Set_Pragma_Identifier (CP, Make_Identifier (Sloc (Prag), Name_Check));
9132 -- If this is inherited case and the current message starts with
9133 -- "failed p", we change it to "failed inherited p...".
9135 if Present (Pspec) then
9137 Msg : constant Node_Id :=
9138 Last (Pragma_Argument_Associations (CP));
9141 if Chars (Msg) = Name_Message then
9142 String_To_Name_Buffer (Strval (Expression (Msg)));
9144 if Name_Buffer (1 .. 8) = "failed p" then
9145 Insert_Str_In_Name_Buffer ("inherited ", 8);
9147 (Expression (Last (Pragma_Argument_Associations (CP))),
9148 String_From_Name_Buffer);
9154 -- Return the check pragma
9159 --------------------------------------
9160 -- Invariants_Or_Predicates_Present --
9161 --------------------------------------
9163 function Invariants_Or_Predicates_Present return Boolean is
9167 -- Check function return result
9169 if Ekind (Designator) /= E_Procedure
9170 and then Has_Invariants (Etype (Designator))
9177 Formal := First_Formal (Designator);
9178 while Present (Formal) loop
9179 if Ekind (Formal) /= E_In_Parameter
9181 (Has_Invariants (Etype (Formal))
9182 or else Present (Predicate_Function (Etype (Formal))))
9187 Next_Formal (Formal);
9191 end Invariants_Or_Predicates_Present;
9193 -- Start of processing for Process_PPCs
9196 -- Capture designator from spec if present, else from body
9198 if Present (Spec_Id) then
9199 Designator := Spec_Id;
9201 Designator := Body_Id;
9204 -- Grab preconditions from spec
9206 if Present (Spec_Id) then
9208 -- Loop through PPC pragmas from spec. Note that preconditions from
9209 -- the body will be analyzed and converted when we scan the body
9210 -- declarations below.
9212 Prag := Spec_PPC_List (Contract (Spec_Id));
9213 while Present (Prag) loop
9214 if Pragma_Name (Prag) = Name_Precondition then
9216 -- For Pre (or Precondition pragma), we simply prepend the
9217 -- pragma to the list of declarations right away so that it
9218 -- will be executed at the start of the procedure. Note that
9219 -- this processing reverses the order of the list, which is
9220 -- what we want since new entries were chained to the head of
9221 -- the list. There can be more than one precondition when we
9222 -- use pragma Precondition.
9224 if not Class_Present (Prag) then
9225 Prepend (Grab_PPC, Declarations (N));
9227 -- For Pre'Class there can only be one pragma, and we save
9228 -- it in Precond for now. We will add inherited Pre'Class
9229 -- stuff before inserting this pragma in the declarations.
9231 Precond := Grab_PPC;
9235 Prag := Next_Pragma (Prag);
9238 -- Now deal with inherited preconditions
9240 for J in Inherited'Range loop
9241 Prag := Spec_PPC_List (Contract (Inherited (J)));
9243 while Present (Prag) loop
9244 if Pragma_Name (Prag) = Name_Precondition
9245 and then Class_Present (Prag)
9247 Inherited_Precond := Grab_PPC (Inherited (J));
9249 -- No precondition so far, so establish this as the first
9251 if No (Precond) then
9252 Precond := Inherited_Precond;
9254 -- Here we already have a precondition, add inherited one
9257 -- Add new precondition to old one using OR ELSE
9260 New_Expr : constant Node_Id :=
9264 (Pragma_Argument_Associations
9265 (Inherited_Precond))));
9266 Old_Expr : constant Node_Id :=
9270 (Pragma_Argument_Associations
9274 if Paren_Count (Old_Expr) = 0 then
9275 Set_Paren_Count (Old_Expr, 1);
9278 if Paren_Count (New_Expr) = 0 then
9279 Set_Paren_Count (New_Expr, 1);
9283 Make_Or_Else (Sloc (Old_Expr),
9284 Left_Opnd => Relocate_Node (Old_Expr),
9285 Right_Opnd => New_Expr));
9288 -- Add new message in the form:
9290 -- failed precondition from bla
9291 -- also failed inherited precondition from bla
9294 -- Skip this if exception locations are suppressed
9296 if not Exception_Locations_Suppressed then
9298 New_Msg : constant Node_Id :=
9301 (Pragma_Argument_Associations
9302 (Inherited_Precond)));
9303 Old_Msg : constant Node_Id :=
9306 (Pragma_Argument_Associations
9309 Start_String (Strval (Old_Msg));
9310 Store_String_Chars (ASCII.LF & " also ");
9311 Store_String_Chars (Strval (New_Msg));
9312 Set_Strval (Old_Msg, End_String);
9318 Prag := Next_Pragma (Prag);
9322 -- If we have built a precondition for Pre'Class (including any
9323 -- Pre'Class aspects inherited from parent subprograms), then we
9324 -- insert this composite precondition at this stage.
9326 if Present (Precond) then
9327 Prepend (Precond, Declarations (N));
9331 -- Build postconditions procedure if needed and prepend the following
9332 -- declaration to the start of the declarations for the subprogram.
9334 -- procedure _postconditions [(_Result : resulttype)] is
9336 -- pragma Check (Postcondition, condition [,message]);
9337 -- pragma Check (Postcondition, condition [,message]);
9339 -- Invariant_Procedure (_Result) ...
9340 -- Invariant_Procedure (Arg1)
9344 -- First we deal with the postconditions in the body
9346 if Is_Non_Empty_List (Declarations (N)) then
9348 -- Loop through declarations
9350 Prag := First (Declarations (N));
9351 while Present (Prag) loop
9352 if Nkind (Prag) = N_Pragma then
9354 -- If pragma, capture if enabled postcondition, else ignore
9356 if Pragma_Name (Prag) = Name_Postcondition
9357 and then Check_Enabled (Name_Postcondition)
9359 if Plist = No_List then
9360 Plist := Empty_List;
9365 -- If expansion is disabled, as in a generic unit, save
9366 -- pragma for later expansion.
9368 if not Expander_Active then
9369 Prepend (Grab_PPC, Declarations (N));
9371 Append (Grab_PPC, Plist);
9377 -- Not a pragma, if comes from source, then end scan
9379 elsif Comes_From_Source (Prag) then
9382 -- Skip stuff not coming from source
9390 -- Now deal with any postconditions from the spec
9392 if Present (Spec_Id) then
9393 Spec_Postconditions : declare
9394 procedure Process_Post_Conditions
9397 -- This processes the Spec_PPC_List from Spec, processing any
9398 -- postconditions from the list. If Class is True, then only
9399 -- postconditions marked with Class_Present are considered.
9400 -- The caller has checked that Spec_PPC_List is non-Empty.
9402 -----------------------------
9403 -- Process_Post_Conditions --
9404 -----------------------------
9406 procedure Process_Post_Conditions
9419 -- Loop through PPC pragmas from spec
9421 Prag := Spec_PPC_List (Contract (Spec));
9423 if Pragma_Name (Prag) = Name_Postcondition
9424 and then (not Class or else Class_Present (Prag))
9426 if Plist = No_List then
9427 Plist := Empty_List;
9430 if not Expander_Active then
9432 (Grab_PPC (Pspec), Declarations (N));
9434 Append (Grab_PPC (Pspec), Plist);
9438 Prag := Next_Pragma (Prag);
9439 exit when No (Prag);
9441 end Process_Post_Conditions;
9443 -- Start of processing for Spec_Postconditions
9446 if Present (Spec_PPC_List (Contract (Spec_Id))) then
9447 Process_Post_Conditions (Spec_Id, Class => False);
9450 -- Process inherited postconditions
9452 for J in Inherited'Range loop
9453 if Present (Spec_PPC_List (Contract (Inherited (J)))) then
9454 Process_Post_Conditions (Inherited (J), Class => True);
9457 end Spec_Postconditions;
9460 -- If we had any postconditions and expansion is enabled, or if the
9461 -- procedure has invariants, then build the _Postconditions procedure.
9463 if (Present (Plist) or else Invariants_Or_Predicates_Present)
9464 and then Expander_Active
9467 Plist := Empty_List;
9470 -- Special processing for function case
9472 if Ekind (Designator) /= E_Procedure then
9474 Rent : constant Entity_Id :=
9475 Make_Defining_Identifier (Loc,
9476 Chars => Name_uResult);
9477 Ftyp : constant Entity_Id := Etype (Designator);
9480 Set_Etype (Rent, Ftyp);
9482 -- Add argument for return
9486 Make_Parameter_Specification (Loc,
9487 Parameter_Type => New_Occurrence_Of (Ftyp, Loc),
9488 Defining_Identifier => Rent));
9490 -- Add invariant call if returning type with invariants
9492 if Has_Invariants (Etype (Rent))
9493 and then Present (Invariant_Procedure (Etype (Rent)))
9496 Make_Invariant_Call (New_Occurrence_Of (Rent, Loc)));
9500 -- Procedure rather than a function
9506 -- Add invariant calls and predicate calls for parameters. Note that
9507 -- this is done for functions as well, since in Ada 2012 they can
9508 -- have IN OUT args.
9515 Formal := First_Formal (Designator);
9516 while Present (Formal) loop
9517 if Ekind (Formal) /= E_In_Parameter then
9518 Ftype := Etype (Formal);
9520 if Has_Invariants (Ftype)
9521 and then Present (Invariant_Procedure (Ftype))
9525 (New_Occurrence_Of (Formal, Loc)));
9528 if Present (Predicate_Function (Ftype)) then
9530 Make_Predicate_Check
9531 (Ftype, New_Occurrence_Of (Formal, Loc)));
9535 Next_Formal (Formal);
9539 -- Build and insert postcondition procedure
9542 Post_Proc : constant Entity_Id :=
9543 Make_Defining_Identifier (Loc,
9544 Chars => Name_uPostconditions);
9545 -- The entity for the _Postconditions procedure
9548 Prepend_To (Declarations (N),
9549 Make_Subprogram_Body (Loc,
9551 Make_Procedure_Specification (Loc,
9552 Defining_Unit_Name => Post_Proc,
9553 Parameter_Specifications => Parms),
9555 Declarations => Empty_List,
9557 Handled_Statement_Sequence =>
9558 Make_Handled_Sequence_Of_Statements (Loc,
9559 Statements => Plist)));
9561 Set_Ekind (Post_Proc, E_Procedure);
9563 -- If this is a procedure, set the Postcondition_Proc attribute on
9564 -- the proper defining entity for the subprogram.
9566 if Ekind (Designator) = E_Procedure then
9567 Set_Postcondition_Proc (Designator, Post_Proc);
9571 Set_Has_Postconditions (Designator);
9575 ----------------------------
9576 -- Reference_Body_Formals --
9577 ----------------------------
9579 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
9584 if Error_Posted (Spec) then
9588 -- Iterate over both lists. They may be of different lengths if the two
9589 -- specs are not conformant.
9591 Fs := First_Formal (Spec);
9592 Fb := First_Formal (Bod);
9593 while Present (Fs) and then Present (Fb) loop
9594 Generate_Reference (Fs, Fb, 'b');
9597 Style.Check_Identifier (Fb, Fs);
9600 Set_Spec_Entity (Fb, Fs);
9601 Set_Referenced (Fs, False);
9605 end Reference_Body_Formals;
9607 -------------------------
9608 -- Set_Actual_Subtypes --
9609 -------------------------
9611 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
9615 First_Stmt : Node_Id := Empty;
9616 AS_Needed : Boolean;
9619 -- If this is an empty initialization procedure, no need to create
9620 -- actual subtypes (small optimization).
9622 if Ekind (Subp) = E_Procedure
9623 and then Is_Null_Init_Proc (Subp)
9628 Formal := First_Formal (Subp);
9629 while Present (Formal) loop
9630 T := Etype (Formal);
9632 -- We never need an actual subtype for a constrained formal
9634 if Is_Constrained (T) then
9637 -- If we have unknown discriminants, then we do not need an actual
9638 -- subtype, or more accurately we cannot figure it out! Note that
9639 -- all class-wide types have unknown discriminants.
9641 elsif Has_Unknown_Discriminants (T) then
9644 -- At this stage we have an unconstrained type that may need an
9645 -- actual subtype. For sure the actual subtype is needed if we have
9646 -- an unconstrained array type.
9648 elsif Is_Array_Type (T) then
9651 -- The only other case needing an actual subtype is an unconstrained
9652 -- record type which is an IN parameter (we cannot generate actual
9653 -- subtypes for the OUT or IN OUT case, since an assignment can
9654 -- change the discriminant values. However we exclude the case of
9655 -- initialization procedures, since discriminants are handled very
9656 -- specially in this context, see the section entitled "Handling of
9657 -- Discriminants" in Einfo.
9659 -- We also exclude the case of Discrim_SO_Functions (functions used
9660 -- in front end layout mode for size/offset values), since in such
9661 -- functions only discriminants are referenced, and not only are such
9662 -- subtypes not needed, but they cannot always be generated, because
9663 -- of order of elaboration issues.
9665 elsif Is_Record_Type (T)
9666 and then Ekind (Formal) = E_In_Parameter
9667 and then Chars (Formal) /= Name_uInit
9668 and then not Is_Unchecked_Union (T)
9669 and then not Is_Discrim_SO_Function (Subp)
9673 -- All other cases do not need an actual subtype
9679 -- Generate actual subtypes for unconstrained arrays and
9680 -- unconstrained discriminated records.
9683 if Nkind (N) = N_Accept_Statement then
9685 -- If expansion is active, The formal is replaced by a local
9686 -- variable that renames the corresponding entry of the
9687 -- parameter block, and it is this local variable that may
9688 -- require an actual subtype.
9690 if Expander_Active then
9691 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
9693 Decl := Build_Actual_Subtype (T, Formal);
9696 if Present (Handled_Statement_Sequence (N)) then
9698 First (Statements (Handled_Statement_Sequence (N)));
9699 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
9700 Mark_Rewrite_Insertion (Decl);
9702 -- If the accept statement has no body, there will be no
9703 -- reference to the actuals, so no need to compute actual
9710 Decl := Build_Actual_Subtype (T, Formal);
9711 Prepend (Decl, Declarations (N));
9712 Mark_Rewrite_Insertion (Decl);
9715 -- The declaration uses the bounds of an existing object, and
9716 -- therefore needs no constraint checks.
9718 Analyze (Decl, Suppress => All_Checks);
9720 -- We need to freeze manually the generated type when it is
9721 -- inserted anywhere else than in a declarative part.
9723 if Present (First_Stmt) then
9724 Insert_List_Before_And_Analyze (First_Stmt,
9725 Freeze_Entity (Defining_Identifier (Decl), N));
9728 if Nkind (N) = N_Accept_Statement
9729 and then Expander_Active
9731 Set_Actual_Subtype (Renamed_Object (Formal),
9732 Defining_Identifier (Decl));
9734 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
9738 Next_Formal (Formal);
9740 end Set_Actual_Subtypes;
9742 ---------------------
9743 -- Set_Formal_Mode --
9744 ---------------------
9746 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
9747 Spec : constant Node_Id := Parent (Formal_Id);
9750 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
9751 -- since we ensure that corresponding actuals are always valid at the
9752 -- point of the call.
9754 if Out_Present (Spec) then
9755 if Ekind (Scope (Formal_Id)) = E_Function
9756 or else Ekind (Scope (Formal_Id)) = E_Generic_Function
9758 -- [IN] OUT parameters allowed for functions in Ada 2012
9760 if Ada_Version >= Ada_2012 then
9761 if In_Present (Spec) then
9762 Set_Ekind (Formal_Id, E_In_Out_Parameter);
9764 Set_Ekind (Formal_Id, E_Out_Parameter);
9767 -- But not in earlier versions of Ada
9770 Error_Msg_N ("functions can only have IN parameters", Spec);
9771 Set_Ekind (Formal_Id, E_In_Parameter);
9774 elsif In_Present (Spec) then
9775 Set_Ekind (Formal_Id, E_In_Out_Parameter);
9778 Set_Ekind (Formal_Id, E_Out_Parameter);
9779 Set_Never_Set_In_Source (Formal_Id, True);
9780 Set_Is_True_Constant (Formal_Id, False);
9781 Set_Current_Value (Formal_Id, Empty);
9785 Set_Ekind (Formal_Id, E_In_Parameter);
9788 -- Set Is_Known_Non_Null for access parameters since the language
9789 -- guarantees that access parameters are always non-null. We also set
9790 -- Can_Never_Be_Null, since there is no way to change the value.
9792 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
9794 -- Ada 2005 (AI-231): In Ada95, access parameters are always non-
9795 -- null; In Ada 2005, only if then null_exclusion is explicit.
9797 if Ada_Version < Ada_2005
9798 or else Can_Never_Be_Null (Etype (Formal_Id))
9800 Set_Is_Known_Non_Null (Formal_Id);
9801 Set_Can_Never_Be_Null (Formal_Id);
9804 -- Ada 2005 (AI-231): Null-exclusion access subtype
9806 elsif Is_Access_Type (Etype (Formal_Id))
9807 and then Can_Never_Be_Null (Etype (Formal_Id))
9809 Set_Is_Known_Non_Null (Formal_Id);
9812 Set_Mechanism (Formal_Id, Default_Mechanism);
9813 Set_Formal_Validity (Formal_Id);
9814 end Set_Formal_Mode;
9816 -------------------------
9817 -- Set_Formal_Validity --
9818 -------------------------
9820 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
9822 -- If no validity checking, then we cannot assume anything about the
9823 -- validity of parameters, since we do not know there is any checking
9824 -- of the validity on the call side.
9826 if not Validity_Checks_On then
9829 -- If validity checking for parameters is enabled, this means we are
9830 -- not supposed to make any assumptions about argument values.
9832 elsif Validity_Check_Parameters then
9835 -- If we are checking in parameters, we will assume that the caller is
9836 -- also checking parameters, so we can assume the parameter is valid.
9838 elsif Ekind (Formal_Id) = E_In_Parameter
9839 and then Validity_Check_In_Params
9841 Set_Is_Known_Valid (Formal_Id, True);
9843 -- Similar treatment for IN OUT parameters
9845 elsif Ekind (Formal_Id) = E_In_Out_Parameter
9846 and then Validity_Check_In_Out_Params
9848 Set_Is_Known_Valid (Formal_Id, True);
9850 end Set_Formal_Validity;
9852 ------------------------
9853 -- Subtype_Conformant --
9854 ------------------------
9856 function Subtype_Conformant
9857 (New_Id : Entity_Id;
9859 Skip_Controlling_Formals : Boolean := False) return Boolean
9863 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
9864 Skip_Controlling_Formals => Skip_Controlling_Formals);
9866 end Subtype_Conformant;
9868 ---------------------
9869 -- Type_Conformant --
9870 ---------------------
9872 function Type_Conformant
9873 (New_Id : Entity_Id;
9875 Skip_Controlling_Formals : Boolean := False) return Boolean
9879 May_Hide_Profile := False;
9882 (New_Id, Old_Id, Type_Conformant, False, Result,
9883 Skip_Controlling_Formals => Skip_Controlling_Formals);
9885 end Type_Conformant;
9887 -------------------------------
9888 -- Valid_Operator_Definition --
9889 -------------------------------
9891 procedure Valid_Operator_Definition (Designator : Entity_Id) is
9894 Id : constant Name_Id := Chars (Designator);
9898 F := First_Formal (Designator);
9899 while Present (F) loop
9902 if Present (Default_Value (F)) then
9904 ("default values not allowed for operator parameters",
9911 -- Verify that user-defined operators have proper number of arguments
9912 -- First case of operators which can only be unary
9915 or else Id = Name_Op_Abs
9919 -- Case of operators which can be unary or binary
9921 elsif Id = Name_Op_Add
9922 or Id = Name_Op_Subtract
9924 N_OK := (N in 1 .. 2);
9926 -- All other operators can only be binary
9934 ("incorrect number of arguments for operator", Designator);
9938 and then Base_Type (Etype (Designator)) = Standard_Boolean
9939 and then not Is_Intrinsic_Subprogram (Designator)
9942 ("explicit definition of inequality not allowed", Designator);
9944 end Valid_Operator_Definition;