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 -- If the return object is of an anonymous access type, then report
568 -- an error if the function's result type is not also anonymous.
570 elsif R_Stm_Type_Is_Anon_Access
571 and then not R_Type_Is_Anon_Access
573 Error_Msg_N ("anonymous access not allowed for function with " &
574 "named access result", Subtype_Ind);
576 -- Subtype indication case: check that the return object's type is
577 -- covered by the result type, and that the subtypes statically match
578 -- when the result subtype is constrained. Also handle record types
579 -- with unknown discriminants for which we have built the underlying
580 -- record view. Coverage is needed to allow specific-type return
581 -- objects when the result type is class-wide (see AI05-32).
583 elsif Covers (Base_Type (R_Type), Base_Type (R_Stm_Type))
584 or else (Is_Underlying_Record_View (Base_Type (R_Stm_Type))
588 Underlying_Record_View (Base_Type (R_Stm_Type))))
590 -- A null exclusion may be present on the return type, on the
591 -- function specification, on the object declaration or on the
594 if Is_Access_Type (R_Type)
596 (Can_Never_Be_Null (R_Type)
597 or else Null_Exclusion_Present (Parent (Scope_Id))) /=
598 Can_Never_Be_Null (R_Stm_Type)
601 ("subtype must statically match function result subtype",
605 -- AI05-103: for elementary types, subtypes must statically match
607 if Is_Constrained (R_Type)
608 or else Is_Access_Type (R_Type)
610 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
612 ("subtype must statically match function result subtype",
617 elsif Etype (Base_Type (R_Type)) = R_Stm_Type
618 and then Is_Null_Extension (Base_Type (R_Type))
624 ("wrong type for return_subtype_indication", Subtype_Ind);
626 end Check_Return_Subtype_Indication;
628 ---------------------
629 -- Local Variables --
630 ---------------------
634 -- Start of processing for Analyze_Function_Return
637 Set_Return_Present (Scope_Id);
639 if Nkind (N) = N_Simple_Return_Statement then
640 Expr := Expression (N);
642 -- Guard against a malformed expression. The parser may have tried to
643 -- recover but the node is not analyzable.
645 if Nkind (Expr) = N_Error then
646 Set_Etype (Expr, Any_Type);
647 Expander_Mode_Save_And_Set (False);
651 -- The resolution of a controlled [extension] aggregate associated
652 -- with a return statement creates a temporary which needs to be
653 -- finalized on function exit. Wrap the return statement inside a
654 -- block so that the finalization machinery can detect this case.
655 -- This early expansion is done only when the return statement is
656 -- not part of a handled sequence of statements.
658 if Nkind_In (Expr, N_Aggregate,
659 N_Extension_Aggregate)
660 and then Needs_Finalization (R_Type)
661 and then Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
664 Make_Block_Statement (Loc,
665 Handled_Statement_Sequence =>
666 Make_Handled_Sequence_Of_Statements (Loc,
667 Statements => New_List (Relocate_Node (N)))));
673 Analyze_And_Resolve (Expr, R_Type);
674 Check_Limited_Return (Expr);
677 -- RETURN only allowed in SPARK as the last statement in function
679 if Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
681 (Nkind (Parent (Parent (N))) /= N_Subprogram_Body
682 or else Present (Next (N)))
684 Check_SPARK_Restriction
685 ("RETURN should be the last statement in function", N);
689 Check_SPARK_Restriction ("extended RETURN is not allowed", N);
691 -- Analyze parts specific to extended_return_statement:
694 Obj_Decl : constant Node_Id :=
695 Last (Return_Object_Declarations (N));
697 HSS : constant Node_Id := Handled_Statement_Sequence (N);
700 Expr := Expression (Obj_Decl);
702 -- Note: The check for OK_For_Limited_Init will happen in
703 -- Analyze_Object_Declaration; we treat it as a normal
704 -- object declaration.
706 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
709 Check_Return_Subtype_Indication (Obj_Decl);
711 if Present (HSS) then
714 if Present (Exception_Handlers (HSS)) then
716 -- ???Has_Nested_Block_With_Handler needs to be set.
717 -- Probably by creating an actual N_Block_Statement.
718 -- Probably in Expand.
724 -- Mark the return object as referenced, since the return is an
725 -- implicit reference of the object.
727 Set_Referenced (Defining_Identifier (Obj_Decl));
729 Check_References (Stm_Entity);
733 -- Case of Expr present
737 -- Defend against previous errors
739 and then Nkind (Expr) /= N_Empty
740 and then Present (Etype (Expr))
742 -- Apply constraint check. Note that this is done before the implicit
743 -- conversion of the expression done for anonymous access types to
744 -- ensure correct generation of the null-excluding check associated
745 -- with null-excluding expressions found in return statements.
747 Apply_Constraint_Check (Expr, R_Type);
749 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
750 -- type, apply an implicit conversion of the expression to that type
751 -- to force appropriate static and run-time accessibility checks.
753 if Ada_Version >= Ada_2005
754 and then Ekind (R_Type) = E_Anonymous_Access_Type
756 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
757 Analyze_And_Resolve (Expr, R_Type);
760 -- If the result type is class-wide, then check that the return
761 -- expression's type is not declared at a deeper level than the
762 -- function (RM05-6.5(5.6/2)).
764 if Ada_Version >= Ada_2005
765 and then Is_Class_Wide_Type (R_Type)
767 if Type_Access_Level (Etype (Expr)) >
768 Subprogram_Access_Level (Scope_Id)
771 ("level of return expression type is deeper than " &
772 "class-wide function!", Expr);
776 -- Check incorrect use of dynamically tagged expression
778 if Is_Tagged_Type (R_Type) then
779 Check_Dynamically_Tagged_Expression
785 -- ??? A real run-time accessibility check is needed in cases
786 -- involving dereferences of access parameters. For now we just
787 -- check the static cases.
789 if (Ada_Version < Ada_2005 or else Debug_Flag_Dot_L)
790 and then Is_Immutably_Limited_Type (Etype (Scope_Id))
791 and then Object_Access_Level (Expr) >
792 Subprogram_Access_Level (Scope_Id)
795 -- Suppress the message in a generic, where the rewriting
798 if Inside_A_Generic then
803 Make_Raise_Program_Error (Loc,
804 Reason => PE_Accessibility_Check_Failed));
808 ("cannot return a local value by reference?", N);
810 ("\& will be raised at run time?",
811 N, Standard_Program_Error);
816 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
817 and then Null_Exclusion_Present (Parent (Scope_Id))
819 Apply_Compile_Time_Constraint_Error
821 Msg => "(Ada 2005) null not allowed for "
822 & "null-excluding return?",
823 Reason => CE_Null_Not_Allowed);
826 -- Apply checks suggested by AI05-0144 (dangerous order dependence)
828 Check_Order_Dependence;
830 end Analyze_Function_Return;
832 -------------------------------------
833 -- Analyze_Generic_Subprogram_Body --
834 -------------------------------------
836 procedure Analyze_Generic_Subprogram_Body
840 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
841 Kind : constant Entity_Kind := Ekind (Gen_Id);
847 -- Copy body and disable expansion while analyzing the generic For a
848 -- stub, do not copy the stub (which would load the proper body), this
849 -- will be done when the proper body is analyzed.
851 if Nkind (N) /= N_Subprogram_Body_Stub then
852 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
857 Spec := Specification (N);
859 -- Within the body of the generic, the subprogram is callable, and
860 -- behaves like the corresponding non-generic unit.
862 Body_Id := Defining_Entity (Spec);
864 if Kind = E_Generic_Procedure
865 and then Nkind (Spec) /= N_Procedure_Specification
867 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
870 elsif Kind = E_Generic_Function
871 and then Nkind (Spec) /= N_Function_Specification
873 Error_Msg_N ("invalid body for generic function ", Body_Id);
877 Set_Corresponding_Body (Gen_Decl, Body_Id);
879 if Has_Completion (Gen_Id)
880 and then Nkind (Parent (N)) /= N_Subunit
882 Error_Msg_N ("duplicate generic body", N);
885 Set_Has_Completion (Gen_Id);
888 if Nkind (N) = N_Subprogram_Body_Stub then
889 Set_Ekind (Defining_Entity (Specification (N)), Kind);
891 Set_Corresponding_Spec (N, Gen_Id);
894 if Nkind (Parent (N)) = N_Compilation_Unit then
895 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
898 -- Make generic parameters immediately visible in the body. They are
899 -- needed to process the formals declarations. Then make the formals
900 -- visible in a separate step.
906 First_Ent : Entity_Id;
909 First_Ent := First_Entity (Gen_Id);
912 while Present (E) and then not Is_Formal (E) loop
917 Set_Use (Generic_Formal_Declarations (Gen_Decl));
919 -- Now generic formals are visible, and the specification can be
920 -- analyzed, for subsequent conformance check.
922 Body_Id := Analyze_Subprogram_Specification (Spec);
924 -- Make formal parameters visible
928 -- E is the first formal parameter, we loop through the formals
929 -- installing them so that they will be visible.
931 Set_First_Entity (Gen_Id, E);
932 while Present (E) loop
938 -- Visible generic entity is callable within its own body
940 Set_Ekind (Gen_Id, Ekind (Body_Id));
941 Set_Ekind (Body_Id, E_Subprogram_Body);
942 Set_Convention (Body_Id, Convention (Gen_Id));
943 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
944 Set_Scope (Body_Id, Scope (Gen_Id));
945 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
947 if Nkind (N) = N_Subprogram_Body_Stub then
949 -- No body to analyze, so restore state of generic unit
951 Set_Ekind (Gen_Id, Kind);
952 Set_Ekind (Body_Id, Kind);
954 if Present (First_Ent) then
955 Set_First_Entity (Gen_Id, First_Ent);
962 -- If this is a compilation unit, it must be made visible explicitly,
963 -- because the compilation of the declaration, unlike other library
964 -- unit declarations, does not. If it is not a unit, the following
965 -- is redundant but harmless.
967 Set_Is_Immediately_Visible (Gen_Id);
968 Reference_Body_Formals (Gen_Id, Body_Id);
970 if Is_Child_Unit (Gen_Id) then
971 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
974 Set_Actual_Subtypes (N, Current_Scope);
976 -- Deal with preconditions and postconditions. In formal verification
977 -- mode, we keep pre- and postconditions attached to entities rather
978 -- than inserted in the code, in order to facilitate a distinct
979 -- treatment for them.
981 if not Alfa_Mode then
982 Process_PPCs (N, Gen_Id, Body_Id);
985 -- If the generic unit carries pre- or post-conditions, copy them
986 -- to the original generic tree, so that they are properly added
987 -- to any instantiation.
990 Orig : constant Node_Id := Original_Node (N);
994 Cond := First (Declarations (N));
995 while Present (Cond) loop
996 if Nkind (Cond) = N_Pragma
997 and then Pragma_Name (Cond) = Name_Check
999 Prepend (New_Copy_Tree (Cond), Declarations (Orig));
1001 elsif Nkind (Cond) = N_Pragma
1002 and then Pragma_Name (Cond) = Name_Postcondition
1004 Set_Ekind (Defining_Entity (Orig), Ekind (Gen_Id));
1005 Prepend (New_Copy_Tree (Cond), Declarations (Orig));
1014 Analyze_Declarations (Declarations (N));
1016 Analyze (Handled_Statement_Sequence (N));
1018 Save_Global_References (Original_Node (N));
1020 -- Prior to exiting the scope, include generic formals again (if any
1021 -- are present) in the set of local entities.
1023 if Present (First_Ent) then
1024 Set_First_Entity (Gen_Id, First_Ent);
1027 Check_References (Gen_Id);
1030 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
1032 Check_Subprogram_Order (N);
1034 -- Outside of its body, unit is generic again
1036 Set_Ekind (Gen_Id, Kind);
1037 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
1040 Style.Check_Identifier (Body_Id, Gen_Id);
1044 end Analyze_Generic_Subprogram_Body;
1046 -----------------------------
1047 -- Analyze_Operator_Symbol --
1048 -----------------------------
1050 -- An operator symbol such as "+" or "and" may appear in context where the
1051 -- literal denotes an entity name, such as "+"(x, y) or in context when it
1052 -- is just a string, as in (conjunction = "or"). In these cases the parser
1053 -- generates this node, and the semantics does the disambiguation. Other
1054 -- such case are actuals in an instantiation, the generic unit in an
1055 -- instantiation, and pragma arguments.
1057 procedure Analyze_Operator_Symbol (N : Node_Id) is
1058 Par : constant Node_Id := Parent (N);
1061 if (Nkind (Par) = N_Function_Call
1062 and then N = Name (Par))
1063 or else Nkind (Par) = N_Function_Instantiation
1064 or else (Nkind (Par) = N_Indexed_Component
1065 and then N = Prefix (Par))
1066 or else (Nkind (Par) = N_Pragma_Argument_Association
1067 and then not Is_Pragma_String_Literal (Par))
1068 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
1069 or else (Nkind (Par) = N_Attribute_Reference
1070 and then Attribute_Name (Par) /= Name_Value)
1072 Find_Direct_Name (N);
1075 Change_Operator_Symbol_To_String_Literal (N);
1078 end Analyze_Operator_Symbol;
1080 -----------------------------------
1081 -- Analyze_Parameter_Association --
1082 -----------------------------------
1084 procedure Analyze_Parameter_Association (N : Node_Id) is
1086 Analyze (Explicit_Actual_Parameter (N));
1087 end Analyze_Parameter_Association;
1089 ----------------------------
1090 -- Analyze_Procedure_Call --
1091 ----------------------------
1093 procedure Analyze_Procedure_Call (N : Node_Id) is
1094 Loc : constant Source_Ptr := Sloc (N);
1095 P : constant Node_Id := Name (N);
1096 Actuals : constant List_Id := Parameter_Associations (N);
1100 procedure Analyze_Call_And_Resolve;
1101 -- Do Analyze and Resolve calls for procedure call
1102 -- At end, check illegal order dependence.
1104 ------------------------------
1105 -- Analyze_Call_And_Resolve --
1106 ------------------------------
1108 procedure Analyze_Call_And_Resolve is
1110 if Nkind (N) = N_Procedure_Call_Statement then
1112 Resolve (N, Standard_Void_Type);
1114 -- Apply checks suggested by AI05-0144
1116 Check_Order_Dependence;
1121 end Analyze_Call_And_Resolve;
1123 -- Start of processing for Analyze_Procedure_Call
1126 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
1127 -- a procedure call or an entry call. The prefix may denote an access
1128 -- to subprogram type, in which case an implicit dereference applies.
1129 -- If the prefix is an indexed component (without implicit dereference)
1130 -- then the construct denotes a call to a member of an entire family.
1131 -- If the prefix is a simple name, it may still denote a call to a
1132 -- parameterless member of an entry family. Resolution of these various
1133 -- interpretations is delicate.
1137 -- If this is a call of the form Obj.Op, the call may have been
1138 -- analyzed and possibly rewritten into a block, in which case
1141 if Analyzed (N) then
1145 -- If there is an error analyzing the name (which may have been
1146 -- rewritten if the original call was in prefix notation) then error
1147 -- has been emitted already, mark node and return.
1150 or else Etype (Name (N)) = Any_Type
1152 Set_Etype (N, Any_Type);
1156 -- Otherwise analyze the parameters
1158 if Present (Actuals) then
1159 Actual := First (Actuals);
1161 while Present (Actual) loop
1163 Check_Parameterless_Call (Actual);
1168 -- Special processing for Elab_Spec, Elab_Body and Elab_Subp_Body calls
1170 if Nkind (P) = N_Attribute_Reference
1171 and then (Attribute_Name (P) = Name_Elab_Spec
1172 or else Attribute_Name (P) = Name_Elab_Body
1173 or else Attribute_Name (P) = Name_Elab_Subp_Body)
1175 if Present (Actuals) then
1177 ("no parameters allowed for this call", First (Actuals));
1181 Set_Etype (N, Standard_Void_Type);
1184 elsif Is_Entity_Name (P)
1185 and then Is_Record_Type (Etype (Entity (P)))
1186 and then Remote_AST_I_Dereference (P)
1190 elsif Is_Entity_Name (P)
1191 and then Ekind (Entity (P)) /= E_Entry_Family
1193 if Is_Access_Type (Etype (P))
1194 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1195 and then No (Actuals)
1196 and then Comes_From_Source (N)
1198 Error_Msg_N ("missing explicit dereference in call", N);
1201 Analyze_Call_And_Resolve;
1203 -- If the prefix is the simple name of an entry family, this is
1204 -- a parameterless call from within the task body itself.
1206 elsif Is_Entity_Name (P)
1207 and then Nkind (P) = N_Identifier
1208 and then Ekind (Entity (P)) = E_Entry_Family
1209 and then Present (Actuals)
1210 and then No (Next (First (Actuals)))
1212 -- Can be call to parameterless entry family. What appears to be the
1213 -- sole argument is in fact the entry index. Rewrite prefix of node
1214 -- accordingly. Source representation is unchanged by this
1218 Make_Indexed_Component (Loc,
1220 Make_Selected_Component (Loc,
1221 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1222 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1223 Expressions => Actuals);
1224 Set_Name (N, New_N);
1225 Set_Etype (New_N, Standard_Void_Type);
1226 Set_Parameter_Associations (N, No_List);
1227 Analyze_Call_And_Resolve;
1229 elsif Nkind (P) = N_Explicit_Dereference then
1230 if Ekind (Etype (P)) = E_Subprogram_Type then
1231 Analyze_Call_And_Resolve;
1233 Error_Msg_N ("expect access to procedure in call", P);
1236 -- The name can be a selected component or an indexed component that
1237 -- yields an access to subprogram. Such a prefix is legal if the call
1238 -- has parameter associations.
1240 elsif Is_Access_Type (Etype (P))
1241 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1243 if Present (Actuals) then
1244 Analyze_Call_And_Resolve;
1246 Error_Msg_N ("missing explicit dereference in call ", N);
1249 -- If not an access to subprogram, then the prefix must resolve to the
1250 -- name of an entry, entry family, or protected operation.
1252 -- For the case of a simple entry call, P is a selected component where
1253 -- the prefix is the task and the selector name is the entry. A call to
1254 -- a protected procedure will have the same syntax. If the protected
1255 -- object contains overloaded operations, the entity may appear as a
1256 -- function, the context will select the operation whose type is Void.
1258 elsif Nkind (P) = N_Selected_Component
1259 and then (Ekind (Entity (Selector_Name (P))) = E_Entry
1261 Ekind (Entity (Selector_Name (P))) = E_Procedure
1263 Ekind (Entity (Selector_Name (P))) = E_Function)
1265 Analyze_Call_And_Resolve;
1267 elsif Nkind (P) = N_Selected_Component
1268 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1269 and then Present (Actuals)
1270 and then No (Next (First (Actuals)))
1272 -- Can be call to parameterless entry family. What appears to be the
1273 -- sole argument is in fact the entry index. Rewrite prefix of node
1274 -- accordingly. Source representation is unchanged by this
1278 Make_Indexed_Component (Loc,
1279 Prefix => New_Copy (P),
1280 Expressions => Actuals);
1281 Set_Name (N, New_N);
1282 Set_Etype (New_N, Standard_Void_Type);
1283 Set_Parameter_Associations (N, No_List);
1284 Analyze_Call_And_Resolve;
1286 -- For the case of a reference to an element of an entry family, P is
1287 -- an indexed component whose prefix is a selected component (task and
1288 -- entry family), and whose index is the entry family index.
1290 elsif Nkind (P) = N_Indexed_Component
1291 and then Nkind (Prefix (P)) = N_Selected_Component
1292 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
1294 Analyze_Call_And_Resolve;
1296 -- If the prefix is the name of an entry family, it is a call from
1297 -- within the task body itself.
1299 elsif Nkind (P) = N_Indexed_Component
1300 and then Nkind (Prefix (P)) = N_Identifier
1301 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
1304 Make_Selected_Component (Loc,
1305 Prefix => New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
1306 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
1307 Rewrite (Prefix (P), New_N);
1309 Analyze_Call_And_Resolve;
1311 -- Anything else is an error
1314 Error_Msg_N ("invalid procedure or entry call", N);
1316 end Analyze_Procedure_Call;
1318 ------------------------------
1319 -- Analyze_Return_Statement --
1320 ------------------------------
1322 procedure Analyze_Return_Statement (N : Node_Id) is
1324 pragma Assert (Nkind_In (N, N_Simple_Return_Statement,
1325 N_Extended_Return_Statement));
1327 Returns_Object : constant Boolean :=
1328 Nkind (N) = N_Extended_Return_Statement
1330 (Nkind (N) = N_Simple_Return_Statement
1331 and then Present (Expression (N)));
1332 -- True if we're returning something; that is, "return <expression>;"
1333 -- or "return Result : T [:= ...]". False for "return;". Used for error
1334 -- checking: If Returns_Object is True, N should apply to a function
1335 -- body; otherwise N should apply to a procedure body, entry body,
1336 -- accept statement, or extended return statement.
1338 function Find_What_It_Applies_To return Entity_Id;
1339 -- Find the entity representing the innermost enclosing body, accept
1340 -- statement, or extended return statement. If the result is a callable
1341 -- construct or extended return statement, then this will be the value
1342 -- of the Return_Applies_To attribute. Otherwise, the program is
1343 -- illegal. See RM-6.5(4/2).
1345 -----------------------------
1346 -- Find_What_It_Applies_To --
1347 -----------------------------
1349 function Find_What_It_Applies_To return Entity_Id is
1350 Result : Entity_Id := Empty;
1353 -- Loop outward through the Scope_Stack, skipping blocks, loops,
1354 -- and postconditions.
1356 for J in reverse 0 .. Scope_Stack.Last loop
1357 Result := Scope_Stack.Table (J).Entity;
1358 exit when not Ekind_In (Result, E_Block, E_Loop)
1359 and then Chars (Result) /= Name_uPostconditions;
1362 pragma Assert (Present (Result));
1364 end Find_What_It_Applies_To;
1366 -- Local declarations
1368 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
1369 Kind : constant Entity_Kind := Ekind (Scope_Id);
1370 Loc : constant Source_Ptr := Sloc (N);
1371 Stm_Entity : constant Entity_Id :=
1373 (E_Return_Statement, Current_Scope, Loc, 'R');
1375 -- Start of processing for Analyze_Return_Statement
1378 Set_Return_Statement_Entity (N, Stm_Entity);
1380 Set_Etype (Stm_Entity, Standard_Void_Type);
1381 Set_Return_Applies_To (Stm_Entity, Scope_Id);
1383 -- Place Return entity on scope stack, to simplify enforcement of 6.5
1384 -- (4/2): an inner return statement will apply to this extended return.
1386 if Nkind (N) = N_Extended_Return_Statement then
1387 Push_Scope (Stm_Entity);
1390 -- Check that pragma No_Return is obeyed. Don't complain about the
1391 -- implicitly-generated return that is placed at the end.
1393 if No_Return (Scope_Id) and then Comes_From_Source (N) then
1394 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
1397 -- Warn on any unassigned OUT parameters if in procedure
1399 if Ekind (Scope_Id) = E_Procedure then
1400 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
1403 -- Check that functions return objects, and other things do not
1405 if Kind = E_Function or else Kind = E_Generic_Function then
1406 if not Returns_Object then
1407 Error_Msg_N ("missing expression in return from function", N);
1410 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
1411 if Returns_Object then
1412 Error_Msg_N ("procedure cannot return value (use function)", N);
1415 elsif Kind = E_Entry or else Kind = E_Entry_Family then
1416 if Returns_Object then
1417 if Is_Protected_Type (Scope (Scope_Id)) then
1418 Error_Msg_N ("entry body cannot return value", N);
1420 Error_Msg_N ("accept statement cannot return value", N);
1424 elsif Kind = E_Return_Statement then
1426 -- We are nested within another return statement, which must be an
1427 -- extended_return_statement.
1429 if Returns_Object then
1431 ("extended_return_statement cannot return value; " &
1432 "use `""RETURN;""`", N);
1436 Error_Msg_N ("illegal context for return statement", N);
1439 if Ekind_In (Kind, E_Function, E_Generic_Function) then
1440 Analyze_Function_Return (N);
1442 elsif Ekind_In (Kind, E_Procedure, E_Generic_Procedure) then
1443 Set_Return_Present (Scope_Id);
1446 if Nkind (N) = N_Extended_Return_Statement then
1450 Kill_Current_Values (Last_Assignment_Only => True);
1451 Check_Unreachable_Code (N);
1452 end Analyze_Return_Statement;
1454 -------------------------------------
1455 -- Analyze_Simple_Return_Statement --
1456 -------------------------------------
1458 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
1460 if Present (Expression (N)) then
1461 Mark_Coextensions (N, Expression (N));
1464 Analyze_Return_Statement (N);
1465 end Analyze_Simple_Return_Statement;
1467 -------------------------
1468 -- Analyze_Return_Type --
1469 -------------------------
1471 procedure Analyze_Return_Type (N : Node_Id) is
1472 Designator : constant Entity_Id := Defining_Entity (N);
1473 Typ : Entity_Id := Empty;
1476 -- Normal case where result definition does not indicate an error
1478 if Result_Definition (N) /= Error then
1479 if Nkind (Result_Definition (N)) = N_Access_Definition then
1480 Check_SPARK_Restriction
1481 ("access result is not allowed", Result_Definition (N));
1483 -- Ada 2005 (AI-254): Handle anonymous access to subprograms
1486 AD : constant Node_Id :=
1487 Access_To_Subprogram_Definition (Result_Definition (N));
1489 if Present (AD) and then Protected_Present (AD) then
1490 Typ := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1492 Typ := Access_Definition (N, Result_Definition (N));
1496 Set_Parent (Typ, Result_Definition (N));
1497 Set_Is_Local_Anonymous_Access (Typ);
1498 Set_Etype (Designator, Typ);
1500 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
1502 Null_Exclusion_Static_Checks (N);
1504 -- Subtype_Mark case
1507 Find_Type (Result_Definition (N));
1508 Typ := Entity (Result_Definition (N));
1509 Set_Etype (Designator, Typ);
1511 -- Unconstrained array as result is not allowed in SPARK
1513 if Is_Array_Type (Typ)
1514 and then not Is_Constrained (Typ)
1516 Check_SPARK_Restriction
1517 ("returning an unconstrained array is not allowed",
1518 Result_Definition (N));
1521 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
1523 Null_Exclusion_Static_Checks (N);
1525 -- If a null exclusion is imposed on the result type, then create
1526 -- a null-excluding itype (an access subtype) and use it as the
1527 -- function's Etype. Note that the null exclusion checks are done
1528 -- right before this, because they don't get applied to types that
1529 -- do not come from source.
1531 if Is_Access_Type (Typ)
1532 and then Null_Exclusion_Present (N)
1534 Set_Etype (Designator,
1535 Create_Null_Excluding_Itype
1538 Scope_Id => Scope (Current_Scope)));
1540 -- The new subtype must be elaborated before use because
1541 -- it is visible outside of the function. However its base
1542 -- type may not be frozen yet, so the reference that will
1543 -- force elaboration must be attached to the freezing of
1546 -- If the return specification appears on a proper body,
1547 -- the subtype will have been created already on the spec.
1549 if Is_Frozen (Typ) then
1550 if Nkind (Parent (N)) = N_Subprogram_Body
1551 and then Nkind (Parent (Parent (N))) = N_Subunit
1555 Build_Itype_Reference (Etype (Designator), Parent (N));
1559 Ensure_Freeze_Node (Typ);
1562 IR : constant Node_Id := Make_Itype_Reference (Sloc (N));
1564 Set_Itype (IR, Etype (Designator));
1565 Append_Freeze_Actions (Typ, New_List (IR));
1570 Set_Etype (Designator, Typ);
1573 if Ekind (Typ) = E_Incomplete_Type
1574 and then Is_Value_Type (Typ)
1578 elsif Ekind (Typ) = E_Incomplete_Type
1579 or else (Is_Class_Wide_Type (Typ)
1581 Ekind (Root_Type (Typ)) = E_Incomplete_Type)
1583 -- AI05-0151: Tagged incomplete types are allowed in all formal
1584 -- parts. Untagged incomplete types are not allowed in bodies.
1586 if Ada_Version >= Ada_2012 then
1587 if Is_Tagged_Type (Typ) then
1590 elsif Nkind_In (Parent (Parent (N)),
1596 ("invalid use of untagged incomplete type&",
1600 -- The type must be completed in the current package. This
1601 -- is checked at the end of the package declaraton, when
1602 -- Taft amemdment types are identified.
1604 if Ekind (Scope (Current_Scope)) = E_Package
1605 and then In_Private_Part (Scope (Current_Scope))
1607 Append_Elmt (Designator, Private_Dependents (Typ));
1612 ("invalid use of incomplete type&", Designator, Typ);
1617 -- Case where result definition does indicate an error
1620 Set_Etype (Designator, Any_Type);
1622 end Analyze_Return_Type;
1624 -----------------------------
1625 -- Analyze_Subprogram_Body --
1626 -----------------------------
1628 procedure Analyze_Subprogram_Body (N : Node_Id) is
1629 Loc : constant Source_Ptr := Sloc (N);
1630 Body_Spec : constant Node_Id := Specification (N);
1631 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
1634 if Debug_Flag_C then
1635 Write_Str ("==> subprogram body ");
1636 Write_Name (Chars (Body_Id));
1637 Write_Str (" from ");
1638 Write_Location (Loc);
1643 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
1645 -- The real work is split out into the helper, so it can do "return;"
1646 -- without skipping the debug output:
1648 Analyze_Subprogram_Body_Helper (N);
1650 if Debug_Flag_C then
1652 Write_Str ("<== subprogram body ");
1653 Write_Name (Chars (Body_Id));
1654 Write_Str (" from ");
1655 Write_Location (Loc);
1658 end Analyze_Subprogram_Body;
1660 ------------------------------------
1661 -- Analyze_Subprogram_Body_Helper --
1662 ------------------------------------
1664 -- This procedure is called for regular subprogram bodies, generic bodies,
1665 -- and for subprogram stubs of both kinds. In the case of stubs, only the
1666 -- specification matters, and is used to create a proper declaration for
1667 -- the subprogram, or to perform conformance checks.
1669 procedure Analyze_Subprogram_Body_Helper (N : Node_Id) is
1670 Loc : constant Source_Ptr := Sloc (N);
1671 Body_Deleted : constant Boolean := False;
1672 Body_Spec : constant Node_Id := Specification (N);
1673 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
1674 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
1675 Conformant : Boolean;
1678 Prot_Typ : Entity_Id := Empty;
1679 Spec_Id : Entity_Id;
1680 Spec_Decl : Node_Id := Empty;
1682 Last_Real_Spec_Entity : Entity_Id := Empty;
1683 -- When we analyze a separate spec, the entity chain ends up containing
1684 -- the formals, as well as any itypes generated during analysis of the
1685 -- default expressions for parameters, or the arguments of associated
1686 -- precondition/postcondition pragmas (which are analyzed in the context
1687 -- of the spec since they have visibility on formals).
1689 -- These entities belong with the spec and not the body. However we do
1690 -- the analysis of the body in the context of the spec (again to obtain
1691 -- visibility to the formals), and all the entities generated during
1692 -- this analysis end up also chained to the entity chain of the spec.
1693 -- But they really belong to the body, and there is circuitry to move
1694 -- them from the spec to the body.
1696 -- However, when we do this move, we don't want to move the real spec
1697 -- entities (first para above) to the body. The Last_Real_Spec_Entity
1698 -- variable points to the last real spec entity, so we only move those
1699 -- chained beyond that point. It is initialized to Empty to deal with
1700 -- the case where there is no separate spec.
1702 procedure Check_Anonymous_Return;
1703 -- Ada 2005: if a function returns an access type that denotes a task,
1704 -- or a type that contains tasks, we must create a master entity for
1705 -- the anonymous type, which typically will be used in an allocator
1706 -- in the body of the function.
1708 procedure Check_Inline_Pragma (Spec : in out Node_Id);
1709 -- Look ahead to recognize a pragma that may appear after the body.
1710 -- If there is a previous spec, check that it appears in the same
1711 -- declarative part. If the pragma is Inline_Always, perform inlining
1712 -- unconditionally, otherwise only if Front_End_Inlining is requested.
1713 -- If the body acts as a spec, and inlining is required, we create a
1714 -- subprogram declaration for it, in order to attach the body to inline.
1715 -- If pragma does not appear after the body, check whether there is
1716 -- an inline pragma before any local declarations.
1718 procedure Check_Missing_Return;
1719 -- Checks for a function with a no return statements, and also performs
1720 -- the warning checks implemented by Check_Returns. In formal mode, also
1721 -- verify that a function ends with a RETURN and that a procedure does
1722 -- not contain any RETURN.
1724 function Disambiguate_Spec return Entity_Id;
1725 -- When a primitive is declared between the private view and the full
1726 -- view of a concurrent type which implements an interface, a special
1727 -- mechanism is used to find the corresponding spec of the primitive
1730 function Is_Private_Concurrent_Primitive
1731 (Subp_Id : Entity_Id) return Boolean;
1732 -- Determine whether subprogram Subp_Id is a primitive of a concurrent
1733 -- type that implements an interface and has a private view.
1735 procedure Set_Trivial_Subprogram (N : Node_Id);
1736 -- Sets the Is_Trivial_Subprogram flag in both spec and body of the
1737 -- subprogram whose body is being analyzed. N is the statement node
1738 -- causing the flag to be set, if the following statement is a return
1739 -- of an entity, we mark the entity as set in source to suppress any
1740 -- warning on the stylized use of function stubs with a dummy return.
1742 procedure Verify_Overriding_Indicator;
1743 -- If there was a previous spec, the entity has been entered in the
1744 -- current scope previously. If the body itself carries an overriding
1745 -- indicator, check that it is consistent with the known status of the
1748 ----------------------------
1749 -- Check_Anonymous_Return --
1750 ----------------------------
1752 procedure Check_Anonymous_Return is
1758 if Present (Spec_Id) then
1764 if Ekind (Scop) = E_Function
1765 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
1766 and then not Is_Thunk (Scop)
1767 and then (Has_Task (Designated_Type (Etype (Scop)))
1769 (Is_Class_Wide_Type (Designated_Type (Etype (Scop)))
1771 Is_Limited_Record (Designated_Type (Etype (Scop)))))
1772 and then Expander_Active
1774 -- Avoid cases with no tasking support
1776 and then RTE_Available (RE_Current_Master)
1777 and then not Restriction_Active (No_Task_Hierarchy)
1780 Make_Object_Declaration (Loc,
1781 Defining_Identifier =>
1782 Make_Defining_Identifier (Loc, Name_uMaster),
1783 Constant_Present => True,
1784 Object_Definition =>
1785 New_Reference_To (RTE (RE_Master_Id), Loc),
1787 Make_Explicit_Dereference (Loc,
1788 New_Reference_To (RTE (RE_Current_Master), Loc)));
1790 if Present (Declarations (N)) then
1791 Prepend (Decl, Declarations (N));
1793 Set_Declarations (N, New_List (Decl));
1796 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
1797 Set_Has_Master_Entity (Scop);
1799 -- Now mark the containing scope as a task master
1802 while Nkind (Par) /= N_Compilation_Unit loop
1803 Par := Parent (Par);
1804 pragma Assert (Present (Par));
1806 -- If we fall off the top, we are at the outer level, and
1807 -- the environment task is our effective master, so nothing
1811 (Par, N_Task_Body, N_Block_Statement, N_Subprogram_Body)
1813 Set_Is_Task_Master (Par, True);
1818 end Check_Anonymous_Return;
1820 -------------------------
1821 -- Check_Inline_Pragma --
1822 -------------------------
1824 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
1828 function Is_Inline_Pragma (N : Node_Id) return Boolean;
1829 -- True when N is a pragma Inline or Inline_Always that applies
1830 -- to this subprogram.
1832 -----------------------
1833 -- Is_Inline_Pragma --
1834 -----------------------
1836 function Is_Inline_Pragma (N : Node_Id) return Boolean is
1839 Nkind (N) = N_Pragma
1841 (Pragma_Name (N) = Name_Inline_Always
1844 and then Pragma_Name (N) = Name_Inline))
1847 (Expression (First (Pragma_Argument_Associations (N))))
1849 end Is_Inline_Pragma;
1851 -- Start of processing for Check_Inline_Pragma
1854 if not Expander_Active then
1858 if Is_List_Member (N)
1859 and then Present (Next (N))
1860 and then Is_Inline_Pragma (Next (N))
1864 elsif Nkind (N) /= N_Subprogram_Body_Stub
1865 and then Present (Declarations (N))
1866 and then Is_Inline_Pragma (First (Declarations (N)))
1868 Prag := First (Declarations (N));
1874 if Present (Prag) then
1875 if Present (Spec_Id) then
1876 if In_Same_List (N, Unit_Declaration_Node (Spec_Id)) then
1881 -- Create a subprogram declaration, to make treatment uniform
1884 Subp : constant Entity_Id :=
1885 Make_Defining_Identifier (Loc, Chars (Body_Id));
1886 Decl : constant Node_Id :=
1887 Make_Subprogram_Declaration (Loc,
1889 New_Copy_Tree (Specification (N)));
1892 Set_Defining_Unit_Name (Specification (Decl), Subp);
1894 if Present (First_Formal (Body_Id)) then
1895 Plist := Copy_Parameter_List (Body_Id);
1896 Set_Parameter_Specifications
1897 (Specification (Decl), Plist);
1900 Insert_Before (N, Decl);
1903 Set_Has_Pragma_Inline (Subp);
1905 if Pragma_Name (Prag) = Name_Inline_Always then
1906 Set_Is_Inlined (Subp);
1907 Set_Has_Pragma_Inline_Always (Subp);
1914 end Check_Inline_Pragma;
1916 --------------------------
1917 -- Check_Missing_Return --
1918 --------------------------
1920 procedure Check_Missing_Return is
1922 Missing_Ret : Boolean;
1925 if Nkind (Body_Spec) = N_Function_Specification then
1926 if Present (Spec_Id) then
1932 if Return_Present (Id) then
1933 Check_Returns (HSS, 'F', Missing_Ret);
1936 Set_Has_Missing_Return (Id);
1939 elsif (Is_Generic_Subprogram (Id)
1940 or else not Is_Machine_Code_Subprogram (Id))
1941 and then not Body_Deleted
1943 Error_Msg_N ("missing RETURN statement in function body", N);
1946 -- If procedure with No_Return, check returns
1948 elsif Nkind (Body_Spec) = N_Procedure_Specification
1949 and then Present (Spec_Id)
1950 and then No_Return (Spec_Id)
1952 Check_Returns (HSS, 'P', Missing_Ret, Spec_Id);
1955 -- Special checks in SPARK mode
1957 if Nkind (Body_Spec) = N_Function_Specification then
1959 -- In SPARK mode, last statement of a function should be a return
1962 Stat : constant Node_Id := Last_Source_Statement (HSS);
1965 and then not Nkind_In (Stat, N_Simple_Return_Statement,
1966 N_Extended_Return_Statement)
1968 Check_SPARK_Restriction
1969 ("last statement in function should be RETURN", Stat);
1973 -- In SPARK mode, verify that a procedure has no return
1975 elsif Nkind (Body_Spec) = N_Procedure_Specification then
1976 if Present (Spec_Id) then
1982 -- Would be nice to point to return statement here, can we
1983 -- borrow the Check_Returns procedure here ???
1985 if Return_Present (Id) then
1986 Check_SPARK_Restriction
1987 ("procedure should not have RETURN", N);
1990 end Check_Missing_Return;
1992 -----------------------
1993 -- Disambiguate_Spec --
1994 -----------------------
1996 function Disambiguate_Spec return Entity_Id is
1997 Priv_Spec : Entity_Id;
2000 procedure Replace_Types (To_Corresponding : Boolean);
2001 -- Depending on the flag, replace the type of formal parameters of
2002 -- Body_Id if it is a concurrent type implementing interfaces with
2003 -- the corresponding record type or the other way around.
2005 procedure Replace_Types (To_Corresponding : Boolean) is
2007 Formal_Typ : Entity_Id;
2010 Formal := First_Formal (Body_Id);
2011 while Present (Formal) loop
2012 Formal_Typ := Etype (Formal);
2014 if Is_Class_Wide_Type (Formal_Typ) then
2015 Formal_Typ := Root_Type (Formal_Typ);
2018 -- From concurrent type to corresponding record
2020 if To_Corresponding then
2021 if Is_Concurrent_Type (Formal_Typ)
2022 and then Present (Corresponding_Record_Type (Formal_Typ))
2023 and then Present (Interfaces (
2024 Corresponding_Record_Type (Formal_Typ)))
2027 Corresponding_Record_Type (Formal_Typ));
2030 -- From corresponding record to concurrent type
2033 if Is_Concurrent_Record_Type (Formal_Typ)
2034 and then Present (Interfaces (Formal_Typ))
2037 Corresponding_Concurrent_Type (Formal_Typ));
2041 Next_Formal (Formal);
2045 -- Start of processing for Disambiguate_Spec
2048 -- Try to retrieve the specification of the body as is. All error
2049 -- messages are suppressed because the body may not have a spec in
2050 -- its current state.
2052 Spec_N := Find_Corresponding_Spec (N, False);
2054 -- It is possible that this is the body of a primitive declared
2055 -- between a private and a full view of a concurrent type. The
2056 -- controlling parameter of the spec carries the concurrent type,
2057 -- not the corresponding record type as transformed by Analyze_
2058 -- Subprogram_Specification. In such cases, we undo the change
2059 -- made by the analysis of the specification and try to find the
2062 -- Note that wrappers already have their corresponding specs and
2063 -- bodies set during their creation, so if the candidate spec is
2064 -- a wrapper, then we definitely need to swap all types to their
2065 -- original concurrent status.
2068 or else Is_Primitive_Wrapper (Spec_N)
2070 -- Restore all references of corresponding record types to the
2071 -- original concurrent types.
2073 Replace_Types (To_Corresponding => False);
2074 Priv_Spec := Find_Corresponding_Spec (N, False);
2076 -- The current body truly belongs to a primitive declared between
2077 -- a private and a full view. We leave the modified body as is,
2078 -- and return the true spec.
2080 if Present (Priv_Spec)
2081 and then Is_Private_Primitive (Priv_Spec)
2086 -- In case that this is some sort of error, restore the original
2087 -- state of the body.
2089 Replace_Types (To_Corresponding => True);
2093 end Disambiguate_Spec;
2095 -------------------------------------
2096 -- Is_Private_Concurrent_Primitive --
2097 -------------------------------------
2099 function Is_Private_Concurrent_Primitive
2100 (Subp_Id : Entity_Id) return Boolean
2102 Formal_Typ : Entity_Id;
2105 if Present (First_Formal (Subp_Id)) then
2106 Formal_Typ := Etype (First_Formal (Subp_Id));
2108 if Is_Concurrent_Record_Type (Formal_Typ) then
2109 if Is_Class_Wide_Type (Formal_Typ) then
2110 Formal_Typ := Root_Type (Formal_Typ);
2113 Formal_Typ := Corresponding_Concurrent_Type (Formal_Typ);
2116 -- The type of the first formal is a concurrent tagged type with
2120 Is_Concurrent_Type (Formal_Typ)
2121 and then Is_Tagged_Type (Formal_Typ)
2122 and then Has_Private_Declaration (Formal_Typ);
2126 end Is_Private_Concurrent_Primitive;
2128 ----------------------------
2129 -- Set_Trivial_Subprogram --
2130 ----------------------------
2132 procedure Set_Trivial_Subprogram (N : Node_Id) is
2133 Nxt : constant Node_Id := Next (N);
2136 Set_Is_Trivial_Subprogram (Body_Id);
2138 if Present (Spec_Id) then
2139 Set_Is_Trivial_Subprogram (Spec_Id);
2143 and then Nkind (Nxt) = N_Simple_Return_Statement
2144 and then No (Next (Nxt))
2145 and then Present (Expression (Nxt))
2146 and then Is_Entity_Name (Expression (Nxt))
2148 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
2150 end Set_Trivial_Subprogram;
2152 ---------------------------------
2153 -- Verify_Overriding_Indicator --
2154 ---------------------------------
2156 procedure Verify_Overriding_Indicator is
2158 if Must_Override (Body_Spec) then
2159 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
2160 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
2164 elsif not Present (Overridden_Operation (Spec_Id)) then
2166 ("subprogram& is not overriding", Body_Spec, Spec_Id);
2169 elsif Must_Not_Override (Body_Spec) then
2170 if Present (Overridden_Operation (Spec_Id)) then
2172 ("subprogram& overrides inherited operation",
2173 Body_Spec, Spec_Id);
2175 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
2176 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
2179 ("subprogram & overrides predefined operator ",
2180 Body_Spec, Spec_Id);
2182 -- If this is not a primitive operation or protected subprogram,
2183 -- then the overriding indicator is altogether illegal.
2185 elsif not Is_Primitive (Spec_Id)
2186 and then Ekind (Scope (Spec_Id)) /= E_Protected_Type
2189 ("overriding indicator only allowed " &
2190 "if subprogram is primitive",
2195 and then Present (Overridden_Operation (Spec_Id))
2197 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
2198 Style.Missing_Overriding (N, Body_Id);
2201 and then Can_Override_Operator (Spec_Id)
2202 and then not Is_Predefined_File_Name
2203 (Unit_File_Name (Get_Source_Unit (Spec_Id)))
2205 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
2206 Style.Missing_Overriding (N, Body_Id);
2208 end Verify_Overriding_Indicator;
2210 -- Start of processing for Analyze_Subprogram_Body_Helper
2213 -- Generic subprograms are handled separately. They always have a
2214 -- generic specification. Determine whether current scope has a
2215 -- previous declaration.
2217 -- If the subprogram body is defined within an instance of the same
2218 -- name, the instance appears as a package renaming, and will be hidden
2219 -- within the subprogram.
2221 if Present (Prev_Id)
2222 and then not Is_Overloadable (Prev_Id)
2223 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
2224 or else Comes_From_Source (Prev_Id))
2226 if Is_Generic_Subprogram (Prev_Id) then
2228 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
2229 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
2231 Analyze_Generic_Subprogram_Body (N, Spec_Id);
2233 if Nkind (N) = N_Subprogram_Body then
2234 HSS := Handled_Statement_Sequence (N);
2235 Check_Missing_Return;
2241 -- Previous entity conflicts with subprogram name. Attempting to
2242 -- enter name will post error.
2244 Enter_Name (Body_Id);
2248 -- Non-generic case, find the subprogram declaration, if one was seen,
2249 -- or enter new overloaded entity in the current scope. If the
2250 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
2251 -- part of the context of one of its subunits. No need to redo the
2254 elsif Prev_Id = Body_Id
2255 and then Has_Completion (Body_Id)
2260 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
2262 if Nkind (N) = N_Subprogram_Body_Stub
2263 or else No (Corresponding_Spec (N))
2265 if Is_Private_Concurrent_Primitive (Body_Id) then
2266 Spec_Id := Disambiguate_Spec;
2268 Spec_Id := Find_Corresponding_Spec (N);
2271 -- If this is a duplicate body, no point in analyzing it
2273 if Error_Posted (N) then
2277 -- A subprogram body should cause freezing of its own declaration,
2278 -- but if there was no previous explicit declaration, then the
2279 -- subprogram will get frozen too late (there may be code within
2280 -- the body that depends on the subprogram having been frozen,
2281 -- such as uses of extra formals), so we force it to be frozen
2282 -- here. Same holds if the body and spec are compilation units.
2283 -- Finally, if the return type is an anonymous access to protected
2284 -- subprogram, it must be frozen before the body because its
2285 -- expansion has generated an equivalent type that is used when
2286 -- elaborating the body.
2288 if No (Spec_Id) then
2289 Freeze_Before (N, Body_Id);
2291 elsif Nkind (Parent (N)) = N_Compilation_Unit then
2292 Freeze_Before (N, Spec_Id);
2294 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
2295 Freeze_Before (N, Etype (Body_Id));
2299 Spec_Id := Corresponding_Spec (N);
2303 -- Do not inline any subprogram that contains nested subprograms, since
2304 -- the backend inlining circuit seems to generate uninitialized
2305 -- references in this case. We know this happens in the case of front
2306 -- end ZCX support, but it also appears it can happen in other cases as
2307 -- well. The backend often rejects attempts to inline in the case of
2308 -- nested procedures anyway, so little if anything is lost by this.
2309 -- Note that this is test is for the benefit of the back-end. There is
2310 -- a separate test for front-end inlining that also rejects nested
2313 -- Do not do this test if errors have been detected, because in some
2314 -- error cases, this code blows up, and we don't need it anyway if
2315 -- there have been errors, since we won't get to the linker anyway.
2317 if Comes_From_Source (Body_Id)
2318 and then Serious_Errors_Detected = 0
2322 P_Ent := Scope (P_Ent);
2323 exit when No (P_Ent) or else P_Ent = Standard_Standard;
2325 if Is_Subprogram (P_Ent) then
2326 Set_Is_Inlined (P_Ent, False);
2328 if Comes_From_Source (P_Ent)
2329 and then Has_Pragma_Inline (P_Ent)
2332 ("cannot inline& (nested subprogram)?",
2339 Check_Inline_Pragma (Spec_Id);
2341 -- Deal with special case of a fully private operation in the body of
2342 -- the protected type. We must create a declaration for the subprogram,
2343 -- in order to attach the protected subprogram that will be used in
2344 -- internal calls. We exclude compiler generated bodies from the
2345 -- expander since the issue does not arise for those cases.
2348 and then Comes_From_Source (N)
2349 and then Is_Protected_Type (Current_Scope)
2351 Spec_Id := Build_Private_Protected_Declaration (N);
2354 -- If a separate spec is present, then deal with freezing issues
2356 if Present (Spec_Id) then
2357 Spec_Decl := Unit_Declaration_Node (Spec_Id);
2358 Verify_Overriding_Indicator;
2360 -- In general, the spec will be frozen when we start analyzing the
2361 -- body. However, for internally generated operations, such as
2362 -- wrapper functions for inherited operations with controlling
2363 -- results, the spec may not have been frozen by the time we expand
2364 -- the freeze actions that include the bodies. In particular, extra
2365 -- formals for accessibility or for return-in-place may need to be
2366 -- generated. Freeze nodes, if any, are inserted before the current
2367 -- body. These freeze actions are also needed in ASIS mode to enable
2368 -- the proper back-annotations.
2370 if not Is_Frozen (Spec_Id)
2371 and then (Expander_Active or ASIS_Mode)
2373 -- Force the generation of its freezing node to ensure proper
2374 -- management of access types in the backend.
2376 -- This is definitely needed for some cases, but it is not clear
2377 -- why, to be investigated further???
2379 Set_Has_Delayed_Freeze (Spec_Id);
2380 Freeze_Before (N, Spec_Id);
2384 -- Mark presence of postcondition procedure in current scope and mark
2385 -- the procedure itself as needing debug info. The latter is important
2386 -- when analyzing decision coverage (for example, for MC/DC coverage).
2388 if Chars (Body_Id) = Name_uPostconditions then
2389 Set_Has_Postconditions (Current_Scope);
2390 Set_Debug_Info_Needed (Body_Id);
2393 -- Place subprogram on scope stack, and make formals visible. If there
2394 -- is a spec, the visible entity remains that of the spec.
2396 if Present (Spec_Id) then
2397 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
2399 if Is_Child_Unit (Spec_Id) then
2400 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
2404 Style.Check_Identifier (Body_Id, Spec_Id);
2407 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
2408 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
2410 if Is_Abstract_Subprogram (Spec_Id) then
2411 Error_Msg_N ("an abstract subprogram cannot have a body", N);
2415 Set_Convention (Body_Id, Convention (Spec_Id));
2416 Set_Has_Completion (Spec_Id);
2418 if Is_Protected_Type (Scope (Spec_Id)) then
2419 Prot_Typ := Scope (Spec_Id);
2422 -- If this is a body generated for a renaming, do not check for
2423 -- full conformance. The check is redundant, because the spec of
2424 -- the body is a copy of the spec in the renaming declaration,
2425 -- and the test can lead to spurious errors on nested defaults.
2427 if Present (Spec_Decl)
2428 and then not Comes_From_Source (N)
2430 (Nkind (Original_Node (Spec_Decl)) =
2431 N_Subprogram_Renaming_Declaration
2432 or else (Present (Corresponding_Body (Spec_Decl))
2434 Nkind (Unit_Declaration_Node
2435 (Corresponding_Body (Spec_Decl))) =
2436 N_Subprogram_Renaming_Declaration))
2440 -- Conversely, the spec may have been generated for specless body
2441 -- with an inline pragma.
2443 elsif Comes_From_Source (N)
2444 and then not Comes_From_Source (Spec_Id)
2445 and then Has_Pragma_Inline (Spec_Id)
2452 Fully_Conformant, True, Conformant, Body_Id);
2455 -- If the body is not fully conformant, we have to decide if we
2456 -- should analyze it or not. If it has a really messed up profile
2457 -- then we probably should not analyze it, since we will get too
2458 -- many bogus messages.
2460 -- Our decision is to go ahead in the non-fully conformant case
2461 -- only if it is at least mode conformant with the spec. Note
2462 -- that the call to Check_Fully_Conformant has issued the proper
2463 -- error messages to complain about the lack of conformance.
2466 and then not Mode_Conformant (Body_Id, Spec_Id)
2472 if Spec_Id /= Body_Id then
2473 Reference_Body_Formals (Spec_Id, Body_Id);
2476 if Nkind (N) /= N_Subprogram_Body_Stub then
2477 Set_Corresponding_Spec (N, Spec_Id);
2479 -- Ada 2005 (AI-345): If the operation is a primitive operation
2480 -- of a concurrent type, the type of the first parameter has been
2481 -- replaced with the corresponding record, which is the proper
2482 -- run-time structure to use. However, within the body there may
2483 -- be uses of the formals that depend on primitive operations
2484 -- of the type (in particular calls in prefixed form) for which
2485 -- we need the original concurrent type. The operation may have
2486 -- several controlling formals, so the replacement must be done
2489 if Comes_From_Source (Spec_Id)
2490 and then Present (First_Entity (Spec_Id))
2491 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
2492 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
2494 Present (Interfaces (Etype (First_Entity (Spec_Id))))
2497 (Corresponding_Concurrent_Type
2498 (Etype (First_Entity (Spec_Id))))
2501 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
2505 Form := First_Formal (Spec_Id);
2506 while Present (Form) loop
2507 if Etype (Form) = Typ then
2508 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
2516 -- Make the formals visible, and place subprogram on scope stack.
2517 -- This is also the point at which we set Last_Real_Spec_Entity
2518 -- to mark the entities which will not be moved to the body.
2520 Install_Formals (Spec_Id);
2521 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
2522 Push_Scope (Spec_Id);
2524 -- Make sure that the subprogram is immediately visible. For
2525 -- child units that have no separate spec this is indispensable.
2526 -- Otherwise it is safe albeit redundant.
2528 Set_Is_Immediately_Visible (Spec_Id);
2531 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
2532 Set_Ekind (Body_Id, E_Subprogram_Body);
2533 Set_Scope (Body_Id, Scope (Spec_Id));
2534 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
2536 -- Case of subprogram body with no previous spec
2539 -- Check for style warning required
2543 -- Only apply check for source level subprograms for which checks
2544 -- have not been suppressed.
2546 and then Comes_From_Source (Body_Id)
2547 and then not Suppress_Style_Checks (Body_Id)
2549 -- No warnings within an instance
2551 and then not In_Instance
2553 -- No warnings for expression functions
2555 and then Nkind (Original_Node (N)) /= N_Expression_Function
2557 Style.Body_With_No_Spec (N);
2560 New_Overloaded_Entity (Body_Id);
2562 if Nkind (N) /= N_Subprogram_Body_Stub then
2563 Set_Acts_As_Spec (N);
2564 Generate_Definition (Body_Id);
2565 Set_Contract (Body_Id, Make_Contract (Sloc (Body_Id)));
2567 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
2568 Generate_Reference_To_Formals (Body_Id);
2569 Install_Formals (Body_Id);
2570 Push_Scope (Body_Id);
2574 -- If the return type is an anonymous access type whose designated type
2575 -- is the limited view of a class-wide type and the non-limited view is
2576 -- available, update the return type accordingly.
2578 if Ada_Version >= Ada_2005
2579 and then Comes_From_Source (N)
2586 Rtyp := Etype (Current_Scope);
2588 if Ekind (Rtyp) = E_Anonymous_Access_Type then
2589 Etyp := Directly_Designated_Type (Rtyp);
2591 if Is_Class_Wide_Type (Etyp)
2592 and then From_With_Type (Etyp)
2594 Set_Directly_Designated_Type
2595 (Etype (Current_Scope), Available_View (Etyp));
2601 -- If this is the proper body of a stub, we must verify that the stub
2602 -- conforms to the body, and to the previous spec if one was present.
2603 -- we know already that the body conforms to that spec. This test is
2604 -- only required for subprograms that come from source.
2606 if Nkind (Parent (N)) = N_Subunit
2607 and then Comes_From_Source (N)
2608 and then not Error_Posted (Body_Id)
2609 and then Nkind (Corresponding_Stub (Parent (N))) =
2610 N_Subprogram_Body_Stub
2613 Old_Id : constant Entity_Id :=
2615 (Specification (Corresponding_Stub (Parent (N))));
2617 Conformant : Boolean := False;
2620 if No (Spec_Id) then
2621 Check_Fully_Conformant (Body_Id, Old_Id);
2625 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
2627 if not Conformant then
2629 -- The stub was taken to be a new declaration. Indicate
2630 -- that it lacks a body.
2632 Set_Has_Completion (Old_Id, False);
2638 Set_Has_Completion (Body_Id);
2639 Check_Eliminated (Body_Id);
2641 if Nkind (N) = N_Subprogram_Body_Stub then
2644 elsif Present (Spec_Id)
2645 and then Expander_Active
2647 (Has_Pragma_Inline_Always (Spec_Id)
2648 or else (Has_Pragma_Inline (Spec_Id) and Front_End_Inlining))
2650 Build_Body_To_Inline (N, Spec_Id);
2653 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
2654 -- if its specification we have to install the private withed units.
2655 -- This holds for child units as well.
2657 if Is_Compilation_Unit (Body_Id)
2658 or else Nkind (Parent (N)) = N_Compilation_Unit
2660 Install_Private_With_Clauses (Body_Id);
2663 Check_Anonymous_Return;
2665 -- Set the Protected_Formal field of each extra formal of the protected
2666 -- subprogram to reference the corresponding extra formal of the
2667 -- subprogram that implements it. For regular formals this occurs when
2668 -- the protected subprogram's declaration is expanded, but the extra
2669 -- formals don't get created until the subprogram is frozen. We need to
2670 -- do this before analyzing the protected subprogram's body so that any
2671 -- references to the original subprogram's extra formals will be changed
2672 -- refer to the implementing subprogram's formals (see Expand_Formal).
2674 if Present (Spec_Id)
2675 and then Is_Protected_Type (Scope (Spec_Id))
2676 and then Present (Protected_Body_Subprogram (Spec_Id))
2679 Impl_Subp : constant Entity_Id :=
2680 Protected_Body_Subprogram (Spec_Id);
2681 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
2682 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
2684 while Present (Prot_Ext_Formal) loop
2685 pragma Assert (Present (Impl_Ext_Formal));
2686 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
2687 Next_Formal_With_Extras (Prot_Ext_Formal);
2688 Next_Formal_With_Extras (Impl_Ext_Formal);
2693 -- Now we can go on to analyze the body
2695 HSS := Handled_Statement_Sequence (N);
2696 Set_Actual_Subtypes (N, Current_Scope);
2698 -- Deal with preconditions and postconditions. In formal verification
2699 -- mode, we keep pre- and postconditions attached to entities rather
2700 -- than inserted in the code, in order to facilitate a distinct
2701 -- treatment for them.
2703 if not Alfa_Mode then
2704 Process_PPCs (N, Spec_Id, Body_Id);
2707 -- Add a declaration for the Protection object, renaming declarations
2708 -- for discriminals and privals and finally a declaration for the entry
2709 -- family index (if applicable). This form of early expansion is done
2710 -- when the Expander is active because Install_Private_Data_Declarations
2711 -- references entities which were created during regular expansion.
2713 if Full_Expander_Active
2714 and then Comes_From_Source (N)
2715 and then Present (Prot_Typ)
2716 and then Present (Spec_Id)
2717 and then not Is_Eliminated (Spec_Id)
2719 Install_Private_Data_Declarations
2720 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
2723 -- Analyze the declarations (this call will analyze the precondition
2724 -- Check pragmas we prepended to the list, as well as the declaration
2725 -- of the _Postconditions procedure).
2727 Analyze_Declarations (Declarations (N));
2729 -- Check completion, and analyze the statements
2732 Inspect_Deferred_Constant_Completion (Declarations (N));
2735 -- Deal with end of scope processing for the body
2737 Process_End_Label (HSS, 't', Current_Scope);
2739 Check_Subprogram_Order (N);
2740 Set_Analyzed (Body_Id);
2742 -- If we have a separate spec, then the analysis of the declarations
2743 -- caused the entities in the body to be chained to the spec id, but
2744 -- we want them chained to the body id. Only the formal parameters
2745 -- end up chained to the spec id in this case.
2747 if Present (Spec_Id) then
2749 -- We must conform to the categorization of our spec
2751 Validate_Categorization_Dependency (N, Spec_Id);
2753 -- And if this is a child unit, the parent units must conform
2755 if Is_Child_Unit (Spec_Id) then
2756 Validate_Categorization_Dependency
2757 (Unit_Declaration_Node (Spec_Id), Spec_Id);
2760 -- Here is where we move entities from the spec to the body
2762 -- Case where there are entities that stay with the spec
2764 if Present (Last_Real_Spec_Entity) then
2766 -- No body entities (happens when the only real spec entities
2767 -- come from precondition and postcondition pragmas)
2769 if No (Last_Entity (Body_Id)) then
2771 (Body_Id, Next_Entity (Last_Real_Spec_Entity));
2773 -- Body entities present (formals), so chain stuff past them
2777 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
2780 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
2781 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
2782 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
2784 -- Case where there are no spec entities, in this case there can
2785 -- be no body entities either, so just move everything.
2788 pragma Assert (No (Last_Entity (Body_Id)));
2789 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
2790 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
2791 Set_First_Entity (Spec_Id, Empty);
2792 Set_Last_Entity (Spec_Id, Empty);
2796 Check_Missing_Return;
2798 -- Now we are going to check for variables that are never modified in
2799 -- the body of the procedure. But first we deal with a special case
2800 -- where we want to modify this check. If the body of the subprogram
2801 -- starts with a raise statement or its equivalent, or if the body
2802 -- consists entirely of a null statement, then it is pretty obvious
2803 -- that it is OK to not reference the parameters. For example, this
2804 -- might be the following common idiom for a stubbed function:
2805 -- statement of the procedure raises an exception. In particular this
2806 -- deals with the common idiom of a stubbed function, which might
2807 -- appear as something like
2809 -- function F (A : Integer) return Some_Type;
2812 -- raise Program_Error;
2816 -- Here the purpose of X is simply to satisfy the annoying requirement
2817 -- in Ada that there be at least one return, and we certainly do not
2818 -- want to go posting warnings on X that it is not initialized! On
2819 -- the other hand, if X is entirely unreferenced that should still
2822 -- What we do is to detect these cases, and if we find them, flag the
2823 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
2824 -- suppress unwanted warnings. For the case of the function stub above
2825 -- we have a special test to set X as apparently assigned to suppress
2832 -- Skip initial labels (for one thing this occurs when we are in
2833 -- front end ZCX mode, but in any case it is irrelevant), and also
2834 -- initial Push_xxx_Error_Label nodes, which are also irrelevant.
2836 Stm := First (Statements (HSS));
2837 while Nkind (Stm) = N_Label
2838 or else Nkind (Stm) in N_Push_xxx_Label
2843 -- Do the test on the original statement before expansion
2846 Ostm : constant Node_Id := Original_Node (Stm);
2849 -- If explicit raise statement, turn on flag
2851 if Nkind (Ostm) = N_Raise_Statement then
2852 Set_Trivial_Subprogram (Stm);
2854 -- If null statement, and no following statements, turn on flag
2856 elsif Nkind (Stm) = N_Null_Statement
2857 and then Comes_From_Source (Stm)
2858 and then No (Next (Stm))
2860 Set_Trivial_Subprogram (Stm);
2862 -- Check for explicit call cases which likely raise an exception
2864 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
2865 if Is_Entity_Name (Name (Ostm)) then
2867 Ent : constant Entity_Id := Entity (Name (Ostm));
2870 -- If the procedure is marked No_Return, then likely it
2871 -- raises an exception, but in any case it is not coming
2872 -- back here, so turn on the flag.
2875 and then Ekind (Ent) = E_Procedure
2876 and then No_Return (Ent)
2878 Set_Trivial_Subprogram (Stm);
2886 -- Check for variables that are never modified
2892 -- If there is a separate spec, then transfer Never_Set_In_Source
2893 -- flags from out parameters to the corresponding entities in the
2894 -- body. The reason we do that is we want to post error flags on
2895 -- the body entities, not the spec entities.
2897 if Present (Spec_Id) then
2898 E1 := First_Entity (Spec_Id);
2899 while Present (E1) loop
2900 if Ekind (E1) = E_Out_Parameter then
2901 E2 := First_Entity (Body_Id);
2902 while Present (E2) loop
2903 exit when Chars (E1) = Chars (E2);
2907 if Present (E2) then
2908 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
2916 -- Check references in body unless it was deleted. Note that the
2917 -- check of Body_Deleted here is not just for efficiency, it is
2918 -- necessary to avoid junk warnings on formal parameters.
2920 if not Body_Deleted then
2921 Check_References (Body_Id);
2924 end Analyze_Subprogram_Body_Helper;
2926 ------------------------------------
2927 -- Analyze_Subprogram_Declaration --
2928 ------------------------------------
2930 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
2931 Loc : constant Source_Ptr := Sloc (N);
2932 Scop : constant Entity_Id := Current_Scope;
2933 Designator : Entity_Id;
2935 Null_Body : Node_Id := Empty;
2937 -- Start of processing for Analyze_Subprogram_Declaration
2940 -- Null procedures are not allowed in SPARK
2942 if Nkind (Specification (N)) = N_Procedure_Specification
2943 and then Null_Present (Specification (N))
2945 Check_SPARK_Restriction ("null procedure is not allowed", N);
2948 -- For a null procedure, capture the profile before analysis, for
2949 -- expansion at the freeze point and at each point of call. The body
2950 -- will only be used if the procedure has preconditions. In that case
2951 -- the body is analyzed at the freeze point.
2953 if Nkind (Specification (N)) = N_Procedure_Specification
2954 and then Null_Present (Specification (N))
2955 and then Expander_Active
2958 Make_Subprogram_Body (Loc,
2960 New_Copy_Tree (Specification (N)),
2963 Handled_Statement_Sequence =>
2964 Make_Handled_Sequence_Of_Statements (Loc,
2965 Statements => New_List (Make_Null_Statement (Loc))));
2967 -- Create new entities for body and formals
2969 Set_Defining_Unit_Name (Specification (Null_Body),
2970 Make_Defining_Identifier (Loc, Chars (Defining_Entity (N))));
2971 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
2973 Form := First (Parameter_Specifications (Specification (Null_Body)));
2974 while Present (Form) loop
2975 Set_Defining_Identifier (Form,
2976 Make_Defining_Identifier (Loc,
2977 Chars (Defining_Identifier (Form))));
2979 -- Resolve the types of the formals now, because the freeze point
2980 -- may appear in a different context, e.g. an instantiation.
2982 if Nkind (Parameter_Type (Form)) /= N_Access_Definition then
2983 Find_Type (Parameter_Type (Form));
2986 No (Access_To_Subprogram_Definition (Parameter_Type (Form)))
2988 Find_Type (Subtype_Mark (Parameter_Type (Form)));
2992 -- the case of a null procedure with a formal that is an
2993 -- access_to_subprogram type, and that is used as an actual
2994 -- in an instantiation is left to the enthusiastic reader.
3002 if Is_Protected_Type (Current_Scope) then
3003 Error_Msg_N ("protected operation cannot be a null procedure", N);
3007 Designator := Analyze_Subprogram_Specification (Specification (N));
3008 Generate_Definition (Designator);
3009 -- ??? why this call, already in Analyze_Subprogram_Specification
3011 if Debug_Flag_C then
3012 Write_Str ("==> subprogram spec ");
3013 Write_Name (Chars (Designator));
3014 Write_Str (" from ");
3015 Write_Location (Sloc (N));
3020 if Nkind (Specification (N)) = N_Procedure_Specification
3021 and then Null_Present (Specification (N))
3023 Set_Has_Completion (Designator);
3025 if Present (Null_Body) then
3026 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
3027 Set_Body_To_Inline (N, Null_Body);
3028 Set_Is_Inlined (Designator);
3032 Validate_RCI_Subprogram_Declaration (N);
3033 New_Overloaded_Entity (Designator);
3034 Check_Delayed_Subprogram (Designator);
3036 -- If the type of the first formal of the current subprogram is a
3037 -- nongeneric tagged private type, mark the subprogram as being a
3038 -- private primitive. Ditto if this is a function with controlling
3039 -- result, and the return type is currently private. In both cases,
3040 -- the type of the controlling argument or result must be in the
3041 -- current scope for the operation to be primitive.
3043 if Has_Controlling_Result (Designator)
3044 and then Is_Private_Type (Etype (Designator))
3045 and then Scope (Etype (Designator)) = Current_Scope
3046 and then not Is_Generic_Actual_Type (Etype (Designator))
3048 Set_Is_Private_Primitive (Designator);
3050 elsif Present (First_Formal (Designator)) then
3052 Formal_Typ : constant Entity_Id :=
3053 Etype (First_Formal (Designator));
3055 Set_Is_Private_Primitive (Designator,
3056 Is_Tagged_Type (Formal_Typ)
3057 and then Scope (Formal_Typ) = Current_Scope
3058 and then Is_Private_Type (Formal_Typ)
3059 and then not Is_Generic_Actual_Type (Formal_Typ));
3063 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
3066 if Ada_Version >= Ada_2005
3067 and then Comes_From_Source (N)
3068 and then Is_Dispatching_Operation (Designator)
3075 if Has_Controlling_Result (Designator) then
3076 Etyp := Etype (Designator);
3079 E := First_Entity (Designator);
3081 and then Is_Formal (E)
3082 and then not Is_Controlling_Formal (E)
3090 if Is_Access_Type (Etyp) then
3091 Etyp := Directly_Designated_Type (Etyp);
3094 if Is_Interface (Etyp)
3095 and then not Is_Abstract_Subprogram (Designator)
3096 and then not (Ekind (Designator) = E_Procedure
3097 and then Null_Present (Specification (N)))
3099 Error_Msg_Name_1 := Chars (Defining_Entity (N));
3101 ("(Ada 2005) interface subprogram % must be abstract or null",
3107 -- What is the following code for, it used to be
3109 -- ??? Set_Suppress_Elaboration_Checks
3110 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
3112 -- The following seems equivalent, but a bit dubious
3114 if Elaboration_Checks_Suppressed (Designator) then
3115 Set_Kill_Elaboration_Checks (Designator);
3118 if Scop /= Standard_Standard
3119 and then not Is_Child_Unit (Designator)
3121 Set_Categorization_From_Scope (Designator, Scop);
3123 -- For a compilation unit, check for library-unit pragmas
3125 Push_Scope (Designator);
3126 Set_Categorization_From_Pragmas (N);
3127 Validate_Categorization_Dependency (N, Designator);
3131 -- For a compilation unit, set body required. This flag will only be
3132 -- reset if a valid Import or Interface pragma is processed later on.
3134 if Nkind (Parent (N)) = N_Compilation_Unit then
3135 Set_Body_Required (Parent (N), True);
3137 if Ada_Version >= Ada_2005
3138 and then Nkind (Specification (N)) = N_Procedure_Specification
3139 and then Null_Present (Specification (N))
3142 ("null procedure cannot be declared at library level", N);
3146 Generate_Reference_To_Formals (Designator);
3147 Check_Eliminated (Designator);
3149 if Debug_Flag_C then
3151 Write_Str ("<== subprogram spec ");
3152 Write_Name (Chars (Designator));
3153 Write_Str (" from ");
3154 Write_Location (Sloc (N));
3158 if Is_Protected_Type (Current_Scope) then
3160 -- Indicate that this is a protected operation, because it may be
3161 -- used in subsequent declarations within the protected type.
3163 Set_Convention (Designator, Convention_Protected);
3166 List_Inherited_Pre_Post_Aspects (Designator);
3168 if Has_Aspects (N) then
3169 Analyze_Aspect_Specifications (N, Designator);
3171 end Analyze_Subprogram_Declaration;
3173 --------------------------------------
3174 -- Analyze_Subprogram_Specification --
3175 --------------------------------------
3177 -- Reminder: N here really is a subprogram specification (not a subprogram
3178 -- declaration). This procedure is called to analyze the specification in
3179 -- both subprogram bodies and subprogram declarations (specs).
3181 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
3182 Designator : constant Entity_Id := Defining_Entity (N);
3183 Formals : constant List_Id := Parameter_Specifications (N);
3185 -- Start of processing for Analyze_Subprogram_Specification
3188 -- User-defined operator is not allowed in SPARK, except as a renaming
3190 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
3191 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
3193 Check_SPARK_Restriction ("user-defined operator is not allowed", N);
3196 -- Proceed with analysis
3198 Generate_Definition (Designator);
3199 Set_Contract (Designator, Make_Contract (Sloc (Designator)));
3201 if Nkind (N) = N_Function_Specification then
3202 Set_Ekind (Designator, E_Function);
3203 Set_Mechanism (Designator, Default_Mechanism);
3205 Set_Ekind (Designator, E_Procedure);
3206 Set_Etype (Designator, Standard_Void_Type);
3209 -- Introduce new scope for analysis of the formals and the return type
3211 Set_Scope (Designator, Current_Scope);
3213 if Present (Formals) then
3214 Push_Scope (Designator);
3215 Process_Formals (Formals, N);
3217 -- Ada 2005 (AI-345): If this is an overriding operation of an
3218 -- inherited interface operation, and the controlling type is
3219 -- a synchronized type, replace the type with its corresponding
3220 -- record, to match the proper signature of an overriding operation.
3221 -- Same processing for an access parameter whose designated type is
3222 -- derived from a synchronized interface.
3224 if Ada_Version >= Ada_2005 then
3227 Formal_Typ : Entity_Id;
3228 Rec_Typ : Entity_Id;
3229 Desig_Typ : Entity_Id;
3232 Formal := First_Formal (Designator);
3233 while Present (Formal) loop
3234 Formal_Typ := Etype (Formal);
3236 if Is_Concurrent_Type (Formal_Typ)
3237 and then Present (Corresponding_Record_Type (Formal_Typ))
3239 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
3241 if Present (Interfaces (Rec_Typ)) then
3242 Set_Etype (Formal, Rec_Typ);
3245 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
3246 Desig_Typ := Designated_Type (Formal_Typ);
3248 if Is_Concurrent_Type (Desig_Typ)
3249 and then Present (Corresponding_Record_Type (Desig_Typ))
3251 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
3253 if Present (Interfaces (Rec_Typ)) then
3254 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
3259 Next_Formal (Formal);
3266 -- The subprogram scope is pushed and popped around the processing of
3267 -- the return type for consistency with call above to Process_Formals
3268 -- (which itself can call Analyze_Return_Type), and to ensure that any
3269 -- itype created for the return type will be associated with the proper
3272 elsif Nkind (N) = N_Function_Specification then
3273 Push_Scope (Designator);
3274 Analyze_Return_Type (N);
3280 if Nkind (N) = N_Function_Specification then
3282 -- Deal with operator symbol case
3284 if Nkind (Designator) = N_Defining_Operator_Symbol then
3285 Valid_Operator_Definition (Designator);
3288 May_Need_Actuals (Designator);
3290 -- Ada 2005 (AI-251): If the return type is abstract, verify that
3291 -- the subprogram is abstract also. This does not apply to renaming
3292 -- declarations, where abstractness is inherited.
3294 -- In case of primitives associated with abstract interface types
3295 -- the check is applied later (see Analyze_Subprogram_Declaration).
3297 if not Nkind_In (Parent (N), N_Subprogram_Renaming_Declaration,
3298 N_Abstract_Subprogram_Declaration,
3299 N_Formal_Abstract_Subprogram_Declaration)
3301 if Is_Abstract_Type (Etype (Designator))
3302 and then not Is_Interface (Etype (Designator))
3305 ("function that returns abstract type must be abstract", N);
3307 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
3308 -- access result whose designated type is abstract.
3310 elsif Nkind (Result_Definition (N)) = N_Access_Definition
3312 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
3313 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
3314 and then Ada_Version >= Ada_2012
3316 Error_Msg_N ("function whose access result designates "
3317 & "abstract type must be abstract", N);
3323 end Analyze_Subprogram_Specification;
3325 --------------------------
3326 -- Build_Body_To_Inline --
3327 --------------------------
3329 procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id) is
3330 Decl : constant Node_Id := Unit_Declaration_Node (Subp);
3331 Original_Body : Node_Id;
3332 Body_To_Analyze : Node_Id;
3333 Max_Size : constant := 10;
3334 Stat_Count : Integer := 0;
3336 function Has_Excluded_Declaration (Decls : List_Id) return Boolean;
3337 -- Check for declarations that make inlining not worthwhile
3339 function Has_Excluded_Statement (Stats : List_Id) return Boolean;
3340 -- Check for statements that make inlining not worthwhile: any tasking
3341 -- statement, nested at any level. Keep track of total number of
3342 -- elementary statements, as a measure of acceptable size.
3344 function Has_Pending_Instantiation return Boolean;
3345 -- If some enclosing body contains instantiations that appear before the
3346 -- corresponding generic body, the enclosing body has a freeze node so
3347 -- that it can be elaborated after the generic itself. This might
3348 -- conflict with subsequent inlinings, so that it is unsafe to try to
3349 -- inline in such a case.
3351 function Has_Single_Return return Boolean;
3352 -- In general we cannot inline functions that return unconstrained type.
3353 -- However, we can handle such functions if all return statements return
3354 -- a local variable that is the only declaration in the body of the
3355 -- function. In that case the call can be replaced by that local
3356 -- variable as is done for other inlined calls.
3358 procedure Remove_Pragmas;
3359 -- A pragma Unreferenced or pragma Unmodified that mentions a formal
3360 -- parameter has no meaning when the body is inlined and the formals
3361 -- are rewritten. Remove it from body to inline. The analysis of the
3362 -- non-inlined body will handle the pragma properly.
3364 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean;
3365 -- If the body of the subprogram includes a call that returns an
3366 -- unconstrained type, the secondary stack is involved, and it
3367 -- is not worth inlining.
3369 ------------------------------
3370 -- Has_Excluded_Declaration --
3371 ------------------------------
3373 function Has_Excluded_Declaration (Decls : List_Id) return Boolean is
3376 function Is_Unchecked_Conversion (D : Node_Id) return Boolean;
3377 -- Nested subprograms make a given body ineligible for inlining, but
3378 -- we make an exception for instantiations of unchecked conversion.
3379 -- The body has not been analyzed yet, so check the name, and verify
3380 -- that the visible entity with that name is the predefined unit.
3382 -----------------------------
3383 -- Is_Unchecked_Conversion --
3384 -----------------------------
3386 function Is_Unchecked_Conversion (D : Node_Id) return Boolean is
3387 Id : constant Node_Id := Name (D);
3391 if Nkind (Id) = N_Identifier
3392 and then Chars (Id) = Name_Unchecked_Conversion
3394 Conv := Current_Entity (Id);
3396 elsif Nkind_In (Id, N_Selected_Component, N_Expanded_Name)
3397 and then Chars (Selector_Name (Id)) = Name_Unchecked_Conversion
3399 Conv := Current_Entity (Selector_Name (Id));
3404 return Present (Conv)
3405 and then Is_Predefined_File_Name
3406 (Unit_File_Name (Get_Source_Unit (Conv)))
3407 and then Is_Intrinsic_Subprogram (Conv);
3408 end Is_Unchecked_Conversion;
3410 -- Start of processing for Has_Excluded_Declaration
3414 while Present (D) loop
3415 if (Nkind (D) = N_Function_Instantiation
3416 and then not Is_Unchecked_Conversion (D))
3417 or else Nkind_In (D, N_Protected_Type_Declaration,
3418 N_Package_Declaration,
3419 N_Package_Instantiation,
3421 N_Procedure_Instantiation,
3422 N_Task_Type_Declaration)
3425 ("cannot inline & (non-allowed declaration)?", D, Subp);
3433 end Has_Excluded_Declaration;
3435 ----------------------------
3436 -- Has_Excluded_Statement --
3437 ----------------------------
3439 function Has_Excluded_Statement (Stats : List_Id) return Boolean is
3445 while Present (S) loop
3446 Stat_Count := Stat_Count + 1;
3448 if Nkind_In (S, N_Abort_Statement,
3449 N_Asynchronous_Select,
3450 N_Conditional_Entry_Call,
3451 N_Delay_Relative_Statement,
3452 N_Delay_Until_Statement,
3457 ("cannot inline & (non-allowed statement)?", S, Subp);
3460 elsif Nkind (S) = N_Block_Statement then
3461 if Present (Declarations (S))
3462 and then Has_Excluded_Declaration (Declarations (S))
3466 elsif Present (Handled_Statement_Sequence (S))
3469 (Exception_Handlers (Handled_Statement_Sequence (S)))
3471 Has_Excluded_Statement
3472 (Statements (Handled_Statement_Sequence (S))))
3477 elsif Nkind (S) = N_Case_Statement then
3478 E := First (Alternatives (S));
3479 while Present (E) loop
3480 if Has_Excluded_Statement (Statements (E)) then
3487 elsif Nkind (S) = N_If_Statement then
3488 if Has_Excluded_Statement (Then_Statements (S)) then
3492 if Present (Elsif_Parts (S)) then
3493 E := First (Elsif_Parts (S));
3494 while Present (E) loop
3495 if Has_Excluded_Statement (Then_Statements (E)) then
3502 if Present (Else_Statements (S))
3503 and then Has_Excluded_Statement (Else_Statements (S))
3508 elsif Nkind (S) = N_Loop_Statement
3509 and then Has_Excluded_Statement (Statements (S))
3513 elsif Nkind (S) = N_Extended_Return_Statement then
3514 if Has_Excluded_Statement
3515 (Statements (Handled_Statement_Sequence (S)))
3517 (Exception_Handlers (Handled_Statement_Sequence (S)))
3527 end Has_Excluded_Statement;
3529 -------------------------------
3530 -- Has_Pending_Instantiation --
3531 -------------------------------
3533 function Has_Pending_Instantiation return Boolean is
3538 while Present (S) loop
3539 if Is_Compilation_Unit (S)
3540 or else Is_Child_Unit (S)
3544 elsif Ekind (S) = E_Package
3545 and then Has_Forward_Instantiation (S)
3554 end Has_Pending_Instantiation;
3556 ------------------------
3557 -- Has_Single_Return --
3558 ------------------------
3560 function Has_Single_Return return Boolean is
3561 Return_Statement : Node_Id := Empty;
3563 function Check_Return (N : Node_Id) return Traverse_Result;
3569 function Check_Return (N : Node_Id) return Traverse_Result is
3571 if Nkind (N) = N_Simple_Return_Statement then
3572 if Present (Expression (N))
3573 and then Is_Entity_Name (Expression (N))
3575 if No (Return_Statement) then
3576 Return_Statement := N;
3579 elsif Chars (Expression (N)) =
3580 Chars (Expression (Return_Statement))
3588 -- A return statement within an extended return is a noop
3591 elsif No (Expression (N))
3592 and then Nkind (Parent (Parent (N))) =
3593 N_Extended_Return_Statement
3598 -- Expression has wrong form
3603 -- We can only inline a build-in-place function if
3604 -- it has a single extended return.
3606 elsif Nkind (N) = N_Extended_Return_Statement then
3607 if No (Return_Statement) then
3608 Return_Statement := N;
3620 function Check_All_Returns is new Traverse_Func (Check_Return);
3622 -- Start of processing for Has_Single_Return
3625 if Check_All_Returns (N) /= OK then
3628 elsif Nkind (Return_Statement) = N_Extended_Return_Statement then
3632 return Present (Declarations (N))
3633 and then Present (First (Declarations (N)))
3634 and then Chars (Expression (Return_Statement)) =
3635 Chars (Defining_Identifier (First (Declarations (N))));
3637 end Has_Single_Return;
3639 --------------------
3640 -- Remove_Pragmas --
3641 --------------------
3643 procedure Remove_Pragmas is
3648 Decl := First (Declarations (Body_To_Analyze));
3649 while Present (Decl) loop
3652 if Nkind (Decl) = N_Pragma
3653 and then (Pragma_Name (Decl) = Name_Unreferenced
3655 Pragma_Name (Decl) = Name_Unmodified)
3664 --------------------------
3665 -- Uses_Secondary_Stack --
3666 --------------------------
3668 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean is
3669 function Check_Call (N : Node_Id) return Traverse_Result;
3670 -- Look for function calls that return an unconstrained type
3676 function Check_Call (N : Node_Id) return Traverse_Result is
3678 if Nkind (N) = N_Function_Call
3679 and then Is_Entity_Name (Name (N))
3680 and then Is_Composite_Type (Etype (Entity (Name (N))))
3681 and then not Is_Constrained (Etype (Entity (Name (N))))
3684 ("cannot inline & (call returns unconstrained type)?",
3692 function Check_Calls is new Traverse_Func (Check_Call);
3695 return Check_Calls (Bod) = Abandon;
3696 end Uses_Secondary_Stack;
3698 -- Start of processing for Build_Body_To_Inline
3701 -- Return immediately if done already
3703 if Nkind (Decl) = N_Subprogram_Declaration
3704 and then Present (Body_To_Inline (Decl))
3708 -- Functions that return unconstrained composite types require
3709 -- secondary stack handling, and cannot currently be inlined, unless
3710 -- all return statements return a local variable that is the first
3711 -- local declaration in the body.
3713 elsif Ekind (Subp) = E_Function
3714 and then not Is_Scalar_Type (Etype (Subp))
3715 and then not Is_Access_Type (Etype (Subp))
3716 and then not Is_Constrained (Etype (Subp))
3718 if not Has_Single_Return then
3720 ("cannot inline & (unconstrained return type)?", N, Subp);
3724 -- Ditto for functions that return controlled types, where controlled
3725 -- actions interfere in complex ways with inlining.
3727 elsif Ekind (Subp) = E_Function
3728 and then Needs_Finalization (Etype (Subp))
3731 ("cannot inline & (controlled return type)?", N, Subp);
3735 if Present (Declarations (N))
3736 and then Has_Excluded_Declaration (Declarations (N))
3741 if Present (Handled_Statement_Sequence (N)) then
3742 if Present (Exception_Handlers (Handled_Statement_Sequence (N))) then
3744 ("cannot inline& (exception handler)?",
3745 First (Exception_Handlers (Handled_Statement_Sequence (N))),
3749 Has_Excluded_Statement
3750 (Statements (Handled_Statement_Sequence (N)))
3756 -- We do not inline a subprogram that is too large, unless it is
3757 -- marked Inline_Always. This pragma does not suppress the other
3758 -- checks on inlining (forbidden declarations, handlers, etc).
3760 if Stat_Count > Max_Size
3761 and then not Has_Pragma_Inline_Always (Subp)
3763 Cannot_Inline ("cannot inline& (body too large)?", N, Subp);
3767 if Has_Pending_Instantiation then
3769 ("cannot inline& (forward instance within enclosing body)?",
3774 -- Within an instance, the body to inline must be treated as a nested
3775 -- generic, so that the proper global references are preserved.
3777 -- Note that we do not do this at the library level, because it is not
3778 -- needed, and furthermore this causes trouble if front end inlining
3779 -- is activated (-gnatN).
3781 if In_Instance and then Scope (Current_Scope) /= Standard_Standard then
3782 Save_Env (Scope (Current_Scope), Scope (Current_Scope));
3783 Original_Body := Copy_Generic_Node (N, Empty, True);
3785 Original_Body := Copy_Separate_Tree (N);
3788 -- We need to capture references to the formals in order to substitute
3789 -- the actuals at the point of inlining, i.e. instantiation. To treat
3790 -- the formals as globals to the body to inline, we nest it within
3791 -- a dummy parameterless subprogram, declared within the real one.
3792 -- To avoid generating an internal name (which is never public, and
3793 -- which affects serial numbers of other generated names), we use
3794 -- an internal symbol that cannot conflict with user declarations.
3796 Set_Parameter_Specifications (Specification (Original_Body), No_List);
3797 Set_Defining_Unit_Name
3798 (Specification (Original_Body),
3799 Make_Defining_Identifier (Sloc (N), Name_uParent));
3800 Set_Corresponding_Spec (Original_Body, Empty);
3802 Body_To_Analyze := Copy_Generic_Node (Original_Body, Empty, False);
3804 -- Set return type of function, which is also global and does not need
3807 if Ekind (Subp) = E_Function then
3808 Set_Result_Definition (Specification (Body_To_Analyze),
3809 New_Occurrence_Of (Etype (Subp), Sloc (N)));
3812 if No (Declarations (N)) then
3813 Set_Declarations (N, New_List (Body_To_Analyze));
3815 Append (Body_To_Analyze, Declarations (N));
3818 Expander_Mode_Save_And_Set (False);
3821 Analyze (Body_To_Analyze);
3822 Push_Scope (Defining_Entity (Body_To_Analyze));
3823 Save_Global_References (Original_Body);
3825 Remove (Body_To_Analyze);
3827 Expander_Mode_Restore;
3829 -- Restore environment if previously saved
3831 if In_Instance and then Scope (Current_Scope) /= Standard_Standard then
3835 -- If secondary stk used there is no point in inlining. We have
3836 -- already issued the warning in this case, so nothing to do.
3838 if Uses_Secondary_Stack (Body_To_Analyze) then
3842 Set_Body_To_Inline (Decl, Original_Body);
3843 Set_Ekind (Defining_Entity (Original_Body), Ekind (Subp));
3844 Set_Is_Inlined (Subp);
3845 end Build_Body_To_Inline;
3851 procedure Cannot_Inline (Msg : String; N : Node_Id; Subp : Entity_Id) is
3853 -- Do not emit warning if this is a predefined unit which is not the
3854 -- main unit. With validity checks enabled, some predefined subprograms
3855 -- may contain nested subprograms and become ineligible for inlining.
3857 if Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (Subp)))
3858 and then not In_Extended_Main_Source_Unit (Subp)
3862 elsif Has_Pragma_Inline_Always (Subp) then
3864 -- Remove last character (question mark) to make this into an error,
3865 -- because the Inline_Always pragma cannot be obeyed.
3867 Error_Msg_NE (Msg (Msg'First .. Msg'Last - 1), N, Subp);
3869 elsif Ineffective_Inline_Warnings then
3870 Error_Msg_NE (Msg, N, Subp);
3874 -----------------------
3875 -- Check_Conformance --
3876 -----------------------
3878 procedure Check_Conformance
3879 (New_Id : Entity_Id;
3881 Ctype : Conformance_Type;
3883 Conforms : out Boolean;
3884 Err_Loc : Node_Id := Empty;
3885 Get_Inst : Boolean := False;
3886 Skip_Controlling_Formals : Boolean := False)
3888 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
3889 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
3890 -- If Errmsg is True, then processing continues to post an error message
3891 -- for conformance error on given node. Two messages are output. The
3892 -- first message points to the previous declaration with a general "no
3893 -- conformance" message. The second is the detailed reason, supplied as
3894 -- Msg. The parameter N provide information for a possible & insertion
3895 -- in the message, and also provides the location for posting the
3896 -- message in the absence of a specified Err_Loc location.
3898 -----------------------
3899 -- Conformance_Error --
3900 -----------------------
3902 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
3909 if No (Err_Loc) then
3915 Error_Msg_Sloc := Sloc (Old_Id);
3918 when Type_Conformant =>
3919 Error_Msg_N -- CODEFIX
3920 ("not type conformant with declaration#!", Enode);
3922 when Mode_Conformant =>
3923 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3925 ("not mode conformant with operation inherited#!",
3929 ("not mode conformant with declaration#!", Enode);
3932 when Subtype_Conformant =>
3933 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3935 ("not subtype conformant with operation inherited#!",
3939 ("not subtype conformant with declaration#!", Enode);
3942 when Fully_Conformant =>
3943 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3944 Error_Msg_N -- CODEFIX
3945 ("not fully conformant with operation inherited#!",
3948 Error_Msg_N -- CODEFIX
3949 ("not fully conformant with declaration#!", Enode);
3953 Error_Msg_NE (Msg, Enode, N);
3955 end Conformance_Error;
3959 Old_Type : constant Entity_Id := Etype (Old_Id);
3960 New_Type : constant Entity_Id := Etype (New_Id);
3961 Old_Formal : Entity_Id;
3962 New_Formal : Entity_Id;
3963 Access_Types_Match : Boolean;
3964 Old_Formal_Base : Entity_Id;
3965 New_Formal_Base : Entity_Id;
3967 -- Start of processing for Check_Conformance
3972 -- We need a special case for operators, since they don't appear
3975 if Ctype = Type_Conformant then
3976 if Ekind (New_Id) = E_Operator
3977 and then Operator_Matches_Spec (New_Id, Old_Id)
3983 -- If both are functions/operators, check return types conform
3985 if Old_Type /= Standard_Void_Type
3986 and then New_Type /= Standard_Void_Type
3989 -- If we are checking interface conformance we omit controlling
3990 -- arguments and result, because we are only checking the conformance
3991 -- of the remaining parameters.
3993 if Has_Controlling_Result (Old_Id)
3994 and then Has_Controlling_Result (New_Id)
3995 and then Skip_Controlling_Formals
3999 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
4000 Conformance_Error ("\return type does not match!", New_Id);
4004 -- Ada 2005 (AI-231): In case of anonymous access types check the
4005 -- null-exclusion and access-to-constant attributes match.
4007 if Ada_Version >= Ada_2005
4008 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
4010 (Can_Never_Be_Null (Old_Type)
4011 /= Can_Never_Be_Null (New_Type)
4012 or else Is_Access_Constant (Etype (Old_Type))
4013 /= Is_Access_Constant (Etype (New_Type)))
4015 Conformance_Error ("\return type does not match!", New_Id);
4019 -- If either is a function/operator and the other isn't, error
4021 elsif Old_Type /= Standard_Void_Type
4022 or else New_Type /= Standard_Void_Type
4024 Conformance_Error ("\functions can only match functions!", New_Id);
4028 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
4029 -- If this is a renaming as body, refine error message to indicate that
4030 -- the conflict is with the original declaration. If the entity is not
4031 -- frozen, the conventions don't have to match, the one of the renamed
4032 -- entity is inherited.
4034 if Ctype >= Subtype_Conformant then
4035 if Convention (Old_Id) /= Convention (New_Id) then
4037 if not Is_Frozen (New_Id) then
4040 elsif Present (Err_Loc)
4041 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
4042 and then Present (Corresponding_Spec (Err_Loc))
4044 Error_Msg_Name_1 := Chars (New_Id);
4046 Name_Ada + Convention_Id'Pos (Convention (New_Id));
4047 Conformance_Error ("\prior declaration for% has convention %!");
4050 Conformance_Error ("\calling conventions do not match!");
4055 elsif Is_Formal_Subprogram (Old_Id)
4056 or else Is_Formal_Subprogram (New_Id)
4058 Conformance_Error ("\formal subprograms not allowed!");
4063 -- Deal with parameters
4065 -- Note: we use the entity information, rather than going directly
4066 -- to the specification in the tree. This is not only simpler, but
4067 -- absolutely necessary for some cases of conformance tests between
4068 -- operators, where the declaration tree simply does not exist!
4070 Old_Formal := First_Formal (Old_Id);
4071 New_Formal := First_Formal (New_Id);
4072 while Present (Old_Formal) and then Present (New_Formal) loop
4073 if Is_Controlling_Formal (Old_Formal)
4074 and then Is_Controlling_Formal (New_Formal)
4075 and then Skip_Controlling_Formals
4077 -- The controlling formals will have different types when
4078 -- comparing an interface operation with its match, but both
4079 -- or neither must be access parameters.
4081 if Is_Access_Type (Etype (Old_Formal))
4083 Is_Access_Type (Etype (New_Formal))
4085 goto Skip_Controlling_Formal;
4088 ("\access parameter does not match!", New_Formal);
4092 if Ctype = Fully_Conformant then
4094 -- Names must match. Error message is more accurate if we do
4095 -- this before checking that the types of the formals match.
4097 if Chars (Old_Formal) /= Chars (New_Formal) then
4098 Conformance_Error ("\name & does not match!", New_Formal);
4100 -- Set error posted flag on new formal as well to stop
4101 -- junk cascaded messages in some cases.
4103 Set_Error_Posted (New_Formal);
4107 -- Null exclusion must match
4109 if Null_Exclusion_Present (Parent (Old_Formal))
4111 Null_Exclusion_Present (Parent (New_Formal))
4113 -- Only give error if both come from source. This should be
4114 -- investigated some time, since it should not be needed ???
4116 if Comes_From_Source (Old_Formal)
4118 Comes_From_Source (New_Formal)
4121 ("\null exclusion for & does not match", New_Formal);
4123 -- Mark error posted on the new formal to avoid duplicated
4124 -- complaint about types not matching.
4126 Set_Error_Posted (New_Formal);
4131 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
4132 -- case occurs whenever a subprogram is being renamed and one of its
4133 -- parameters imposes a null exclusion. For example:
4135 -- type T is null record;
4136 -- type Acc_T is access T;
4137 -- subtype Acc_T_Sub is Acc_T;
4139 -- procedure P (Obj : not null Acc_T_Sub); -- itype
4140 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
4143 Old_Formal_Base := Etype (Old_Formal);
4144 New_Formal_Base := Etype (New_Formal);
4147 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
4148 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
4151 Access_Types_Match := Ada_Version >= Ada_2005
4153 -- Ensure that this rule is only applied when New_Id is a
4154 -- renaming of Old_Id.
4156 and then Nkind (Parent (Parent (New_Id))) =
4157 N_Subprogram_Renaming_Declaration
4158 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
4159 and then Present (Entity (Name (Parent (Parent (New_Id)))))
4160 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
4162 -- Now handle the allowed access-type case
4164 and then Is_Access_Type (Old_Formal_Base)
4165 and then Is_Access_Type (New_Formal_Base)
4167 -- The type kinds must match. The only exception occurs with
4168 -- multiple generics of the form:
4171 -- type F is private; type A is private;
4172 -- type F_Ptr is access F; type A_Ptr is access A;
4173 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
4174 -- package F_Pack is ... package A_Pack is
4175 -- package F_Inst is
4176 -- new F_Pack (A, A_Ptr, A_P);
4178 -- When checking for conformance between the parameters of A_P
4179 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
4180 -- because the compiler has transformed A_Ptr into a subtype of
4181 -- F_Ptr. We catch this case in the code below.
4183 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
4185 (Is_Generic_Type (Old_Formal_Base)
4186 and then Is_Generic_Type (New_Formal_Base)
4187 and then Is_Internal (New_Formal_Base)
4188 and then Etype (Etype (New_Formal_Base)) =
4190 and then Directly_Designated_Type (Old_Formal_Base) =
4191 Directly_Designated_Type (New_Formal_Base)
4192 and then ((Is_Itype (Old_Formal_Base)
4193 and then Can_Never_Be_Null (Old_Formal_Base))
4195 (Is_Itype (New_Formal_Base)
4196 and then Can_Never_Be_Null (New_Formal_Base)));
4198 -- Types must always match. In the visible part of an instance,
4199 -- usual overloading rules for dispatching operations apply, and
4200 -- we check base types (not the actual subtypes).
4202 if In_Instance_Visible_Part
4203 and then Is_Dispatching_Operation (New_Id)
4205 if not Conforming_Types
4206 (T1 => Base_Type (Etype (Old_Formal)),
4207 T2 => Base_Type (Etype (New_Formal)),
4209 Get_Inst => Get_Inst)
4210 and then not Access_Types_Match
4212 Conformance_Error ("\type of & does not match!", New_Formal);
4216 elsif not Conforming_Types
4217 (T1 => Old_Formal_Base,
4218 T2 => New_Formal_Base,
4220 Get_Inst => Get_Inst)
4221 and then not Access_Types_Match
4223 -- Don't give error message if old type is Any_Type. This test
4224 -- avoids some cascaded errors, e.g. in case of a bad spec.
4226 if Errmsg and then Old_Formal_Base = Any_Type then
4229 Conformance_Error ("\type of & does not match!", New_Formal);
4235 -- For mode conformance, mode must match
4237 if Ctype >= Mode_Conformant then
4238 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
4239 if not Ekind_In (New_Id, E_Function, E_Procedure)
4240 or else not Is_Primitive_Wrapper (New_Id)
4242 Conformance_Error ("\mode of & does not match!", New_Formal);
4246 T : constant Entity_Id := Find_Dispatching_Type (New_Id);
4248 if Is_Protected_Type
4249 (Corresponding_Concurrent_Type (T))
4251 Error_Msg_PT (T, New_Id);
4254 ("\mode of & does not match!", New_Formal);
4261 -- Part of mode conformance for access types is having the same
4262 -- constant modifier.
4264 elsif Access_Types_Match
4265 and then Is_Access_Constant (Old_Formal_Base) /=
4266 Is_Access_Constant (New_Formal_Base)
4269 ("\constant modifier does not match!", New_Formal);
4274 if Ctype >= Subtype_Conformant then
4276 -- Ada 2005 (AI-231): In case of anonymous access types check
4277 -- the null-exclusion and access-to-constant attributes must
4278 -- match. For null exclusion, we test the types rather than the
4279 -- formals themselves, since the attribute is only set reliably
4280 -- on the formals in the Ada 95 case, and we exclude the case
4281 -- where Old_Formal is marked as controlling, to avoid errors
4282 -- when matching completing bodies with dispatching declarations
4283 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
4285 if Ada_Version >= Ada_2005
4286 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
4287 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
4289 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
4290 Can_Never_Be_Null (Etype (New_Formal))
4292 not Is_Controlling_Formal (Old_Formal))
4294 Is_Access_Constant (Etype (Old_Formal)) /=
4295 Is_Access_Constant (Etype (New_Formal)))
4297 -- Do not complain if error already posted on New_Formal. This
4298 -- avoids some redundant error messages.
4300 and then not Error_Posted (New_Formal)
4302 -- It is allowed to omit the null-exclusion in case of stream
4303 -- attribute subprograms. We recognize stream subprograms
4304 -- through their TSS-generated suffix.
4307 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
4309 if TSS_Name /= TSS_Stream_Read
4310 and then TSS_Name /= TSS_Stream_Write
4311 and then TSS_Name /= TSS_Stream_Input
4312 and then TSS_Name /= TSS_Stream_Output
4315 ("\type of & does not match!", New_Formal);
4322 -- Full conformance checks
4324 if Ctype = Fully_Conformant then
4326 -- We have checked already that names match
4328 if Parameter_Mode (Old_Formal) = E_In_Parameter then
4330 -- Check default expressions for in parameters
4333 NewD : constant Boolean :=
4334 Present (Default_Value (New_Formal));
4335 OldD : constant Boolean :=
4336 Present (Default_Value (Old_Formal));
4338 if NewD or OldD then
4340 -- The old default value has been analyzed because the
4341 -- current full declaration will have frozen everything
4342 -- before. The new default value has not been analyzed,
4343 -- so analyze it now before we check for conformance.
4346 Push_Scope (New_Id);
4347 Preanalyze_Spec_Expression
4348 (Default_Value (New_Formal), Etype (New_Formal));
4352 if not (NewD and OldD)
4353 or else not Fully_Conformant_Expressions
4354 (Default_Value (Old_Formal),
4355 Default_Value (New_Formal))
4358 ("\default expression for & does not match!",
4367 -- A couple of special checks for Ada 83 mode. These checks are
4368 -- skipped if either entity is an operator in package Standard,
4369 -- or if either old or new instance is not from the source program.
4371 if Ada_Version = Ada_83
4372 and then Sloc (Old_Id) > Standard_Location
4373 and then Sloc (New_Id) > Standard_Location
4374 and then Comes_From_Source (Old_Id)
4375 and then Comes_From_Source (New_Id)
4378 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
4379 New_Param : constant Node_Id := Declaration_Node (New_Formal);
4382 -- Explicit IN must be present or absent in both cases. This
4383 -- test is required only in the full conformance case.
4385 if In_Present (Old_Param) /= In_Present (New_Param)
4386 and then Ctype = Fully_Conformant
4389 ("\(Ada 83) IN must appear in both declarations",
4394 -- Grouping (use of comma in param lists) must be the same
4395 -- This is where we catch a misconformance like:
4398 -- A : Integer; B : Integer
4400 -- which are represented identically in the tree except
4401 -- for the setting of the flags More_Ids and Prev_Ids.
4403 if More_Ids (Old_Param) /= More_Ids (New_Param)
4404 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
4407 ("\grouping of & does not match!", New_Formal);
4413 -- This label is required when skipping controlling formals
4415 <<Skip_Controlling_Formal>>
4417 Next_Formal (Old_Formal);
4418 Next_Formal (New_Formal);
4421 if Present (Old_Formal) then
4422 Conformance_Error ("\too few parameters!");
4425 elsif Present (New_Formal) then
4426 Conformance_Error ("\too many parameters!", New_Formal);
4429 end Check_Conformance;
4431 -----------------------
4432 -- Check_Conventions --
4433 -----------------------
4435 procedure Check_Conventions (Typ : Entity_Id) is
4436 Ifaces_List : Elist_Id;
4438 procedure Check_Convention (Op : Entity_Id);
4439 -- Verify that the convention of inherited dispatching operation Op is
4440 -- consistent among all subprograms it overrides. In order to minimize
4441 -- the search, Search_From is utilized to designate a specific point in
4442 -- the list rather than iterating over the whole list once more.
4444 ----------------------
4445 -- Check_Convention --
4446 ----------------------
4448 procedure Check_Convention (Op : Entity_Id) is
4449 Iface_Elmt : Elmt_Id;
4450 Iface_Prim_Elmt : Elmt_Id;
4451 Iface_Prim : Entity_Id;
4454 Iface_Elmt := First_Elmt (Ifaces_List);
4455 while Present (Iface_Elmt) loop
4457 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
4458 while Present (Iface_Prim_Elmt) loop
4459 Iface_Prim := Node (Iface_Prim_Elmt);
4461 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
4462 and then Convention (Iface_Prim) /= Convention (Op)
4465 ("inconsistent conventions in primitive operations", Typ);
4467 Error_Msg_Name_1 := Chars (Op);
4468 Error_Msg_Name_2 := Get_Convention_Name (Convention (Op));
4469 Error_Msg_Sloc := Sloc (Op);
4471 if Comes_From_Source (Op) or else No (Alias (Op)) then
4472 if not Present (Overridden_Operation (Op)) then
4473 Error_Msg_N ("\\primitive % defined #", Typ);
4476 ("\\overriding operation % with " &
4477 "convention % defined #", Typ);
4480 else pragma Assert (Present (Alias (Op)));
4481 Error_Msg_Sloc := Sloc (Alias (Op));
4483 ("\\inherited operation % with " &
4484 "convention % defined #", Typ);
4487 Error_Msg_Name_1 := Chars (Op);
4489 Get_Convention_Name (Convention (Iface_Prim));
4490 Error_Msg_Sloc := Sloc (Iface_Prim);
4492 ("\\overridden operation % with " &
4493 "convention % defined #", Typ);
4495 -- Avoid cascading errors
4500 Next_Elmt (Iface_Prim_Elmt);
4503 Next_Elmt (Iface_Elmt);
4505 end Check_Convention;
4509 Prim_Op : Entity_Id;
4510 Prim_Op_Elmt : Elmt_Id;
4512 -- Start of processing for Check_Conventions
4515 if not Has_Interfaces (Typ) then
4519 Collect_Interfaces (Typ, Ifaces_List);
4521 -- The algorithm checks every overriding dispatching operation against
4522 -- all the corresponding overridden dispatching operations, detecting
4523 -- differences in conventions.
4525 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
4526 while Present (Prim_Op_Elmt) loop
4527 Prim_Op := Node (Prim_Op_Elmt);
4529 -- A small optimization: skip the predefined dispatching operations
4530 -- since they always have the same convention.
4532 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
4533 Check_Convention (Prim_Op);
4536 Next_Elmt (Prim_Op_Elmt);
4538 end Check_Conventions;
4540 ------------------------------
4541 -- Check_Delayed_Subprogram --
4542 ------------------------------
4544 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
4547 procedure Possible_Freeze (T : Entity_Id);
4548 -- T is the type of either a formal parameter or of the return type.
4549 -- If T is not yet frozen and needs a delayed freeze, then the
4550 -- subprogram itself must be delayed. If T is the limited view of an
4551 -- incomplete type the subprogram must be frozen as well, because
4552 -- T may depend on local types that have not been frozen yet.
4554 ---------------------
4555 -- Possible_Freeze --
4556 ---------------------
4558 procedure Possible_Freeze (T : Entity_Id) is
4560 if Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
4561 Set_Has_Delayed_Freeze (Designator);
4563 elsif Is_Access_Type (T)
4564 and then Has_Delayed_Freeze (Designated_Type (T))
4565 and then not Is_Frozen (Designated_Type (T))
4567 Set_Has_Delayed_Freeze (Designator);
4569 elsif Ekind (T) = E_Incomplete_Type and then From_With_Type (T) then
4570 Set_Has_Delayed_Freeze (Designator);
4572 -- AI05-0151: In Ada 2012, Incomplete types can appear in the profile
4573 -- of a subprogram or entry declaration.
4575 elsif Ekind (T) = E_Incomplete_Type
4576 and then Ada_Version >= Ada_2012
4578 Set_Has_Delayed_Freeze (Designator);
4581 end Possible_Freeze;
4583 -- Start of processing for Check_Delayed_Subprogram
4586 -- All subprograms, including abstract subprograms, may need a freeze
4587 -- node if some formal type or the return type needs one.
4589 Possible_Freeze (Etype (Designator));
4590 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
4592 -- Need delayed freeze if any of the formal types themselves need
4593 -- a delayed freeze and are not yet frozen.
4595 F := First_Formal (Designator);
4596 while Present (F) loop
4597 Possible_Freeze (Etype (F));
4598 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
4602 -- Mark functions that return by reference. Note that it cannot be
4603 -- done for delayed_freeze subprograms because the underlying
4604 -- returned type may not be known yet (for private types)
4606 if not Has_Delayed_Freeze (Designator)
4607 and then Expander_Active
4610 Typ : constant Entity_Id := Etype (Designator);
4611 Utyp : constant Entity_Id := Underlying_Type (Typ);
4614 if Is_Immutably_Limited_Type (Typ) then
4615 Set_Returns_By_Ref (Designator);
4617 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
4618 Set_Returns_By_Ref (Designator);
4622 end Check_Delayed_Subprogram;
4624 ------------------------------------
4625 -- Check_Discriminant_Conformance --
4626 ------------------------------------
4628 procedure Check_Discriminant_Conformance
4633 Old_Discr : Entity_Id := First_Discriminant (Prev);
4634 New_Discr : Node_Id := First (Discriminant_Specifications (N));
4635 New_Discr_Id : Entity_Id;
4636 New_Discr_Type : Entity_Id;
4638 procedure Conformance_Error (Msg : String; N : Node_Id);
4639 -- Post error message for conformance error on given node. Two messages
4640 -- are output. The first points to the previous declaration with a
4641 -- general "no conformance" message. The second is the detailed reason,
4642 -- supplied as Msg. The parameter N provide information for a possible
4643 -- & insertion in the message.
4645 -----------------------
4646 -- Conformance_Error --
4647 -----------------------
4649 procedure Conformance_Error (Msg : String; N : Node_Id) is
4651 Error_Msg_Sloc := Sloc (Prev_Loc);
4652 Error_Msg_N -- CODEFIX
4653 ("not fully conformant with declaration#!", N);
4654 Error_Msg_NE (Msg, N, N);
4655 end Conformance_Error;
4657 -- Start of processing for Check_Discriminant_Conformance
4660 while Present (Old_Discr) and then Present (New_Discr) loop
4662 New_Discr_Id := Defining_Identifier (New_Discr);
4664 -- The subtype mark of the discriminant on the full type has not
4665 -- been analyzed so we do it here. For an access discriminant a new
4668 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
4670 Access_Definition (N, Discriminant_Type (New_Discr));
4673 Analyze (Discriminant_Type (New_Discr));
4674 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
4676 -- Ada 2005: if the discriminant definition carries a null
4677 -- exclusion, create an itype to check properly for consistency
4678 -- with partial declaration.
4680 if Is_Access_Type (New_Discr_Type)
4681 and then Null_Exclusion_Present (New_Discr)
4684 Create_Null_Excluding_Itype
4685 (T => New_Discr_Type,
4686 Related_Nod => New_Discr,
4687 Scope_Id => Current_Scope);
4691 if not Conforming_Types
4692 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
4694 Conformance_Error ("type of & does not match!", New_Discr_Id);
4697 -- Treat the new discriminant as an occurrence of the old one,
4698 -- for navigation purposes, and fill in some semantic
4699 -- information, for completeness.
4701 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
4702 Set_Etype (New_Discr_Id, Etype (Old_Discr));
4703 Set_Scope (New_Discr_Id, Scope (Old_Discr));
4708 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
4709 Conformance_Error ("name & does not match!", New_Discr_Id);
4713 -- Default expressions must match
4716 NewD : constant Boolean :=
4717 Present (Expression (New_Discr));
4718 OldD : constant Boolean :=
4719 Present (Expression (Parent (Old_Discr)));
4722 if NewD or OldD then
4724 -- The old default value has been analyzed and expanded,
4725 -- because the current full declaration will have frozen
4726 -- everything before. The new default values have not been
4727 -- expanded, so expand now to check conformance.
4730 Preanalyze_Spec_Expression
4731 (Expression (New_Discr), New_Discr_Type);
4734 if not (NewD and OldD)
4735 or else not Fully_Conformant_Expressions
4736 (Expression (Parent (Old_Discr)),
4737 Expression (New_Discr))
4741 ("default expression for & does not match!",
4748 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
4750 if Ada_Version = Ada_83 then
4752 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
4755 -- Grouping (use of comma in param lists) must be the same
4756 -- This is where we catch a misconformance like:
4759 -- A : Integer; B : Integer
4761 -- which are represented identically in the tree except
4762 -- for the setting of the flags More_Ids and Prev_Ids.
4764 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
4765 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
4768 ("grouping of & does not match!", New_Discr_Id);
4774 Next_Discriminant (Old_Discr);
4778 if Present (Old_Discr) then
4779 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
4782 elsif Present (New_Discr) then
4784 ("too many discriminants!", Defining_Identifier (New_Discr));
4787 end Check_Discriminant_Conformance;
4789 ----------------------------
4790 -- Check_Fully_Conformant --
4791 ----------------------------
4793 procedure Check_Fully_Conformant
4794 (New_Id : Entity_Id;
4796 Err_Loc : Node_Id := Empty)
4799 pragma Warnings (Off, Result);
4802 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
4803 end Check_Fully_Conformant;
4805 ---------------------------
4806 -- Check_Mode_Conformant --
4807 ---------------------------
4809 procedure Check_Mode_Conformant
4810 (New_Id : Entity_Id;
4812 Err_Loc : Node_Id := Empty;
4813 Get_Inst : Boolean := False)
4816 pragma Warnings (Off, Result);
4819 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
4820 end Check_Mode_Conformant;
4822 --------------------------------
4823 -- Check_Overriding_Indicator --
4824 --------------------------------
4826 procedure Check_Overriding_Indicator
4828 Overridden_Subp : Entity_Id;
4829 Is_Primitive : Boolean)
4835 -- No overriding indicator for literals
4837 if Ekind (Subp) = E_Enumeration_Literal then
4840 elsif Ekind (Subp) = E_Entry then
4841 Decl := Parent (Subp);
4843 -- No point in analyzing a malformed operator
4845 elsif Nkind (Subp) = N_Defining_Operator_Symbol
4846 and then Error_Posted (Subp)
4851 Decl := Unit_Declaration_Node (Subp);
4854 if Nkind_In (Decl, N_Subprogram_Body,
4855 N_Subprogram_Body_Stub,
4856 N_Subprogram_Declaration,
4857 N_Abstract_Subprogram_Declaration,
4858 N_Subprogram_Renaming_Declaration)
4860 Spec := Specification (Decl);
4862 elsif Nkind (Decl) = N_Entry_Declaration then
4869 -- The overriding operation is type conformant with the overridden one,
4870 -- but the names of the formals are not required to match. If the names
4871 -- appear permuted in the overriding operation, this is a possible
4872 -- source of confusion that is worth diagnosing. Controlling formals
4873 -- often carry names that reflect the type, and it is not worthwhile
4874 -- requiring that their names match.
4876 if Present (Overridden_Subp)
4877 and then Nkind (Subp) /= N_Defining_Operator_Symbol
4884 Form1 := First_Formal (Subp);
4885 Form2 := First_Formal (Overridden_Subp);
4887 -- If the overriding operation is a synchronized operation, skip
4888 -- the first parameter of the overridden operation, which is
4889 -- implicit in the new one. If the operation is declared in the
4890 -- body it is not primitive and all formals must match.
4892 if Is_Concurrent_Type (Scope (Subp))
4893 and then Is_Tagged_Type (Scope (Subp))
4894 and then not Has_Completion (Scope (Subp))
4896 Form2 := Next_Formal (Form2);
4899 if Present (Form1) then
4900 Form1 := Next_Formal (Form1);
4901 Form2 := Next_Formal (Form2);
4904 while Present (Form1) loop
4905 if not Is_Controlling_Formal (Form1)
4906 and then Present (Next_Formal (Form2))
4907 and then Chars (Form1) = Chars (Next_Formal (Form2))
4909 Error_Msg_Node_2 := Alias (Overridden_Subp);
4910 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
4912 ("& does not match corresponding formal of&#",
4917 Next_Formal (Form1);
4918 Next_Formal (Form2);
4923 -- If there is an overridden subprogram, then check that there is no
4924 -- "not overriding" indicator, and mark the subprogram as overriding.
4925 -- This is not done if the overridden subprogram is marked as hidden,
4926 -- which can occur for the case of inherited controlled operations
4927 -- (see Derive_Subprogram), unless the inherited subprogram's parent
4928 -- subprogram is not itself hidden. (Note: This condition could probably
4929 -- be simplified, leaving out the testing for the specific controlled
4930 -- cases, but it seems safer and clearer this way, and echoes similar
4931 -- special-case tests of this kind in other places.)
4933 if Present (Overridden_Subp)
4934 and then (not Is_Hidden (Overridden_Subp)
4936 ((Chars (Overridden_Subp) = Name_Initialize
4938 Chars (Overridden_Subp) = Name_Adjust
4940 Chars (Overridden_Subp) = Name_Finalize)
4941 and then Present (Alias (Overridden_Subp))
4942 and then not Is_Hidden (Alias (Overridden_Subp))))
4944 if Must_Not_Override (Spec) then
4945 Error_Msg_Sloc := Sloc (Overridden_Subp);
4947 if Ekind (Subp) = E_Entry then
4949 ("entry & overrides inherited operation #", Spec, Subp);
4952 ("subprogram & overrides inherited operation #", Spec, Subp);
4955 elsif Is_Subprogram (Subp) then
4956 if Is_Init_Proc (Subp) then
4959 elsif No (Overridden_Operation (Subp)) then
4961 -- For entities generated by Derive_Subprograms the overridden
4962 -- operation is the inherited primitive (which is available
4963 -- through the attribute alias)
4965 if (Is_Dispatching_Operation (Subp)
4966 or else Is_Dispatching_Operation (Overridden_Subp))
4967 and then not Comes_From_Source (Overridden_Subp)
4968 and then Find_Dispatching_Type (Overridden_Subp) =
4969 Find_Dispatching_Type (Subp)
4970 and then Present (Alias (Overridden_Subp))
4971 and then Comes_From_Source (Alias (Overridden_Subp))
4973 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
4976 Set_Overridden_Operation (Subp, Overridden_Subp);
4981 -- If primitive flag is set or this is a protected operation, then
4982 -- the operation is overriding at the point of its declaration, so
4983 -- warn if necessary. Otherwise it may have been declared before the
4984 -- operation it overrides and no check is required.
4987 and then not Must_Override (Spec)
4988 and then (Is_Primitive
4989 or else Ekind (Scope (Subp)) = E_Protected_Type)
4991 Style.Missing_Overriding (Decl, Subp);
4994 -- If Subp is an operator, it may override a predefined operation, if
4995 -- it is defined in the same scope as the type to which it applies.
4996 -- In that case Overridden_Subp is empty because of our implicit
4997 -- representation for predefined operators. We have to check whether the
4998 -- signature of Subp matches that of a predefined operator. Note that
4999 -- first argument provides the name of the operator, and the second
5000 -- argument the signature that may match that of a standard operation.
5001 -- If the indicator is overriding, then the operator must match a
5002 -- predefined signature, because we know already that there is no
5003 -- explicit overridden operation.
5005 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
5006 if Must_Not_Override (Spec) then
5008 -- If this is not a primitive or a protected subprogram, then
5009 -- "not overriding" is illegal.
5012 and then Ekind (Scope (Subp)) /= E_Protected_Type
5015 ("overriding indicator only allowed "
5016 & "if subprogram is primitive", Subp);
5018 elsif Can_Override_Operator (Subp) then
5020 ("subprogram& overrides predefined operator ", Spec, Subp);
5023 elsif Must_Override (Spec) then
5024 if No (Overridden_Operation (Subp))
5025 and then not Can_Override_Operator (Subp)
5027 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
5030 elsif not Error_Posted (Subp)
5031 and then Style_Check
5032 and then Can_Override_Operator (Subp)
5034 not Is_Predefined_File_Name
5035 (Unit_File_Name (Get_Source_Unit (Subp)))
5037 -- If style checks are enabled, indicate that the indicator is
5038 -- missing. However, at the point of declaration, the type of
5039 -- which this is a primitive operation may be private, in which
5040 -- case the indicator would be premature.
5042 if Has_Private_Declaration (Etype (Subp))
5043 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
5047 Style.Missing_Overriding (Decl, Subp);
5051 elsif Must_Override (Spec) then
5052 if Ekind (Subp) = E_Entry then
5053 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
5055 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
5058 -- If the operation is marked "not overriding" and it's not primitive
5059 -- then an error is issued, unless this is an operation of a task or
5060 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
5061 -- has been specified have already been checked above.
5063 elsif Must_Not_Override (Spec)
5064 and then not Is_Primitive
5065 and then Ekind (Subp) /= E_Entry
5066 and then Ekind (Scope (Subp)) /= E_Protected_Type
5069 ("overriding indicator only allowed if subprogram is primitive",
5073 end Check_Overriding_Indicator;
5079 -- Note: this procedure needs to know far too much about how the expander
5080 -- messes with exceptions. The use of the flag Exception_Junk and the
5081 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
5082 -- works, but is not very clean. It would be better if the expansion
5083 -- routines would leave Original_Node working nicely, and we could use
5084 -- Original_Node here to ignore all the peculiar expander messing ???
5086 procedure Check_Returns
5090 Proc : Entity_Id := Empty)
5094 procedure Check_Statement_Sequence (L : List_Id);
5095 -- Internal recursive procedure to check a list of statements for proper
5096 -- termination by a return statement (or a transfer of control or a
5097 -- compound statement that is itself internally properly terminated).
5099 ------------------------------
5100 -- Check_Statement_Sequence --
5101 ------------------------------
5103 procedure Check_Statement_Sequence (L : List_Id) is
5108 Raise_Exception_Call : Boolean;
5109 -- Set True if statement sequence terminated by Raise_Exception call
5110 -- or a Reraise_Occurrence call.
5113 Raise_Exception_Call := False;
5115 -- Get last real statement
5117 Last_Stm := Last (L);
5119 -- Deal with digging out exception handler statement sequences that
5120 -- have been transformed by the local raise to goto optimization.
5121 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
5122 -- optimization has occurred, we are looking at something like:
5125 -- original stmts in block
5129 -- goto L1; | omitted if No_Exception_Propagation
5134 -- goto L3; -- skip handler when exception not raised
5136 -- <<L1>> -- target label for local exception
5150 -- and what we have to do is to dig out the estmts1 and estmts2
5151 -- sequences (which were the original sequences of statements in
5152 -- the exception handlers) and check them.
5154 if Nkind (Last_Stm) = N_Label
5155 and then Exception_Junk (Last_Stm)
5161 exit when Nkind (Stm) /= N_Block_Statement;
5162 exit when not Exception_Junk (Stm);
5165 exit when Nkind (Stm) /= N_Label;
5166 exit when not Exception_Junk (Stm);
5167 Check_Statement_Sequence
5168 (Statements (Handled_Statement_Sequence (Next (Stm))));
5173 exit when Nkind (Stm) /= N_Goto_Statement;
5174 exit when not Exception_Junk (Stm);
5178 -- Don't count pragmas
5180 while Nkind (Last_Stm) = N_Pragma
5182 -- Don't count call to SS_Release (can happen after Raise_Exception)
5185 (Nkind (Last_Stm) = N_Procedure_Call_Statement
5187 Nkind (Name (Last_Stm)) = N_Identifier
5189 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
5191 -- Don't count exception junk
5194 (Nkind_In (Last_Stm, N_Goto_Statement,
5196 N_Object_Declaration)
5197 and then Exception_Junk (Last_Stm))
5198 or else Nkind (Last_Stm) in N_Push_xxx_Label
5199 or else Nkind (Last_Stm) in N_Pop_xxx_Label
5204 -- Here we have the "real" last statement
5206 Kind := Nkind (Last_Stm);
5208 -- Transfer of control, OK. Note that in the No_Return procedure
5209 -- case, we already diagnosed any explicit return statements, so
5210 -- we can treat them as OK in this context.
5212 if Is_Transfer (Last_Stm) then
5215 -- Check cases of explicit non-indirect procedure calls
5217 elsif Kind = N_Procedure_Call_Statement
5218 and then Is_Entity_Name (Name (Last_Stm))
5220 -- Check call to Raise_Exception procedure which is treated
5221 -- specially, as is a call to Reraise_Occurrence.
5223 -- We suppress the warning in these cases since it is likely that
5224 -- the programmer really does not expect to deal with the case
5225 -- of Null_Occurrence, and thus would find a warning about a
5226 -- missing return curious, and raising Program_Error does not
5227 -- seem such a bad behavior if this does occur.
5229 -- Note that in the Ada 2005 case for Raise_Exception, the actual
5230 -- behavior will be to raise Constraint_Error (see AI-329).
5232 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
5234 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
5236 Raise_Exception_Call := True;
5238 -- For Raise_Exception call, test first argument, if it is
5239 -- an attribute reference for a 'Identity call, then we know
5240 -- that the call cannot possibly return.
5243 Arg : constant Node_Id :=
5244 Original_Node (First_Actual (Last_Stm));
5246 if Nkind (Arg) = N_Attribute_Reference
5247 and then Attribute_Name (Arg) = Name_Identity
5254 -- If statement, need to look inside if there is an else and check
5255 -- each constituent statement sequence for proper termination.
5257 elsif Kind = N_If_Statement
5258 and then Present (Else_Statements (Last_Stm))
5260 Check_Statement_Sequence (Then_Statements (Last_Stm));
5261 Check_Statement_Sequence (Else_Statements (Last_Stm));
5263 if Present (Elsif_Parts (Last_Stm)) then
5265 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
5268 while Present (Elsif_Part) loop
5269 Check_Statement_Sequence (Then_Statements (Elsif_Part));
5277 -- Case statement, check each case for proper termination
5279 elsif Kind = N_Case_Statement then
5283 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
5284 while Present (Case_Alt) loop
5285 Check_Statement_Sequence (Statements (Case_Alt));
5286 Next_Non_Pragma (Case_Alt);
5292 -- Block statement, check its handled sequence of statements
5294 elsif Kind = N_Block_Statement then
5300 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
5309 -- Loop statement. If there is an iteration scheme, we can definitely
5310 -- fall out of the loop. Similarly if there is an exit statement, we
5311 -- can fall out. In either case we need a following return.
5313 elsif Kind = N_Loop_Statement then
5314 if Present (Iteration_Scheme (Last_Stm))
5315 or else Has_Exit (Entity (Identifier (Last_Stm)))
5319 -- A loop with no exit statement or iteration scheme is either
5320 -- an infinite loop, or it has some other exit (raise/return).
5321 -- In either case, no warning is required.
5327 -- Timed entry call, check entry call and delay alternatives
5329 -- Note: in expanded code, the timed entry call has been converted
5330 -- to a set of expanded statements on which the check will work
5331 -- correctly in any case.
5333 elsif Kind = N_Timed_Entry_Call then
5335 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
5336 DCA : constant Node_Id := Delay_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 -- If statement sequence of delay alternative is missing, then
5347 -- we can definitely fall through, and we post the error
5348 -- message on the delay alternative itself.
5350 -- Note: if both ECA and DCA are missing the return, then we
5351 -- post only one message, should be enough to fix the bugs.
5352 -- If not we will get a message next time on the DCA when the
5355 elsif No (Statements (DCA)) then
5358 -- Else check both statement sequences
5361 Check_Statement_Sequence (Statements (ECA));
5362 Check_Statement_Sequence (Statements (DCA));
5367 -- Conditional entry call, check entry call and else part
5369 -- Note: in expanded code, the conditional entry call has been
5370 -- converted to a set of expanded statements on which the check
5371 -- will work correctly in any case.
5373 elsif Kind = N_Conditional_Entry_Call then
5375 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
5378 -- If statement sequence of entry call alternative is missing,
5379 -- then we can definitely fall through, and we post the error
5380 -- message on the entry call alternative itself.
5382 if No (Statements (ECA)) then
5385 -- Else check statement sequence and else part
5388 Check_Statement_Sequence (Statements (ECA));
5389 Check_Statement_Sequence (Else_Statements (Last_Stm));
5395 -- If we fall through, issue appropriate message
5398 if not Raise_Exception_Call then
5400 ("?RETURN statement missing following this statement!",
5403 ("\?Program_Error may be raised at run time!",
5407 -- Note: we set Err even though we have not issued a warning
5408 -- because we still have a case of a missing return. This is
5409 -- an extremely marginal case, probably will never be noticed
5410 -- but we might as well get it right.
5414 -- Otherwise we have the case of a procedure marked No_Return
5417 if not Raise_Exception_Call then
5419 ("?implied return after this statement " &
5420 "will raise Program_Error",
5423 ("\?procedure & is marked as No_Return!",
5428 RE : constant Node_Id :=
5429 Make_Raise_Program_Error (Sloc (Last_Stm),
5430 Reason => PE_Implicit_Return);
5432 Insert_After (Last_Stm, RE);
5436 end Check_Statement_Sequence;
5438 -- Start of processing for Check_Returns
5442 Check_Statement_Sequence (Statements (HSS));
5444 if Present (Exception_Handlers (HSS)) then
5445 Handler := First_Non_Pragma (Exception_Handlers (HSS));
5446 while Present (Handler) loop
5447 Check_Statement_Sequence (Statements (Handler));
5448 Next_Non_Pragma (Handler);
5453 ----------------------------
5454 -- Check_Subprogram_Order --
5455 ----------------------------
5457 procedure Check_Subprogram_Order (N : Node_Id) is
5459 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
5460 -- This is used to check if S1 > S2 in the sense required by this
5461 -- test, for example nameab < namec, but name2 < name10.
5463 -----------------------------
5464 -- Subprogram_Name_Greater --
5465 -----------------------------
5467 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
5472 -- Remove trailing numeric parts
5475 while S1 (L1) in '0' .. '9' loop
5480 while S2 (L2) in '0' .. '9' loop
5484 -- If non-numeric parts non-equal, that's decisive
5486 if S1 (S1'First .. L1) < S2 (S2'First .. L2) then
5489 elsif S1 (S1'First .. L1) > S2 (S2'First .. L2) then
5492 -- If non-numeric parts equal, compare suffixed numeric parts. Note
5493 -- that a missing suffix is treated as numeric zero in this test.
5497 while L1 < S1'Last loop
5499 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
5503 while L2 < S2'Last loop
5505 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
5510 end Subprogram_Name_Greater;
5512 -- Start of processing for Check_Subprogram_Order
5515 -- Check body in alpha order if this is option
5518 and then Style_Check_Order_Subprograms
5519 and then Nkind (N) = N_Subprogram_Body
5520 and then Comes_From_Source (N)
5521 and then In_Extended_Main_Source_Unit (N)
5525 renames Scope_Stack.Table
5526 (Scope_Stack.Last).Last_Subprogram_Name;
5528 Body_Id : constant Entity_Id :=
5529 Defining_Entity (Specification (N));
5532 Get_Decoded_Name_String (Chars (Body_Id));
5535 if Subprogram_Name_Greater
5536 (LSN.all, Name_Buffer (1 .. Name_Len))
5538 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
5544 LSN := new String'(Name_Buffer (1 .. Name_Len));
5547 end Check_Subprogram_Order;
5549 ------------------------------
5550 -- Check_Subtype_Conformant --
5551 ------------------------------
5553 procedure Check_Subtype_Conformant
5554 (New_Id : Entity_Id;
5556 Err_Loc : Node_Id := Empty;
5557 Skip_Controlling_Formals : Boolean := False)
5560 pragma Warnings (Off, Result);
5563 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
5564 Skip_Controlling_Formals => Skip_Controlling_Formals);
5565 end Check_Subtype_Conformant;
5567 ---------------------------
5568 -- Check_Type_Conformant --
5569 ---------------------------
5571 procedure Check_Type_Conformant
5572 (New_Id : Entity_Id;
5574 Err_Loc : Node_Id := Empty)
5577 pragma Warnings (Off, Result);
5580 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
5581 end Check_Type_Conformant;
5583 ---------------------------
5584 -- Can_Override_Operator --
5585 ---------------------------
5587 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
5590 if Nkind (Subp) /= N_Defining_Operator_Symbol then
5594 Typ := Base_Type (Etype (First_Formal (Subp)));
5596 return Operator_Matches_Spec (Subp, Subp)
5597 and then Scope (Subp) = Scope (Typ)
5598 and then not Is_Class_Wide_Type (Typ);
5600 end Can_Override_Operator;
5602 ----------------------
5603 -- Conforming_Types --
5604 ----------------------
5606 function Conforming_Types
5609 Ctype : Conformance_Type;
5610 Get_Inst : Boolean := False) return Boolean
5612 Type_1 : Entity_Id := T1;
5613 Type_2 : Entity_Id := T2;
5614 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
5616 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean;
5617 -- If neither T1 nor T2 are generic actual types, or if they are in
5618 -- different scopes (e.g. parent and child instances), then verify that
5619 -- the base types are equal. Otherwise T1 and T2 must be on the same
5620 -- subtype chain. The whole purpose of this procedure is to prevent
5621 -- spurious ambiguities in an instantiation that may arise if two
5622 -- distinct generic types are instantiated with the same actual.
5624 function Find_Designated_Type (T : Entity_Id) return Entity_Id;
5625 -- An access parameter can designate an incomplete type. If the
5626 -- incomplete type is the limited view of a type from a limited_
5627 -- with_clause, check whether the non-limited view is available. If
5628 -- it is a (non-limited) incomplete type, get the full view.
5630 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean;
5631 -- Returns True if and only if either T1 denotes a limited view of T2
5632 -- or T2 denotes a limited view of T1. This can arise when the limited
5633 -- with view of a type is used in a subprogram declaration and the
5634 -- subprogram body is in the scope of a regular with clause for the
5635 -- same unit. In such a case, the two type entities can be considered
5636 -- identical for purposes of conformance checking.
5638 ----------------------
5639 -- Base_Types_Match --
5640 ----------------------
5642 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean is
5647 elsif Base_Type (T1) = Base_Type (T2) then
5649 -- The following is too permissive. A more precise test should
5650 -- check that the generic actual is an ancestor subtype of the
5653 return not Is_Generic_Actual_Type (T1)
5654 or else not Is_Generic_Actual_Type (T2)
5655 or else Scope (T1) /= Scope (T2);
5660 end Base_Types_Match;
5662 --------------------------
5663 -- Find_Designated_Type --
5664 --------------------------
5666 function Find_Designated_Type (T : Entity_Id) return Entity_Id is
5670 Desig := Directly_Designated_Type (T);
5672 if Ekind (Desig) = E_Incomplete_Type then
5674 -- If regular incomplete type, get full view if available
5676 if Present (Full_View (Desig)) then
5677 Desig := Full_View (Desig);
5679 -- If limited view of a type, get non-limited view if available,
5680 -- and check again for a regular incomplete type.
5682 elsif Present (Non_Limited_View (Desig)) then
5683 Desig := Get_Full_View (Non_Limited_View (Desig));
5688 end Find_Designated_Type;
5690 -------------------------------
5691 -- Matches_Limited_With_View --
5692 -------------------------------
5694 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean is
5696 -- In some cases a type imported through a limited_with clause, and
5697 -- its nonlimited view are both visible, for example in an anonymous
5698 -- access-to-class-wide type in a formal. Both entities designate the
5701 if From_With_Type (T1)
5702 and then T2 = Available_View (T1)
5706 elsif From_With_Type (T2)
5707 and then T1 = Available_View (T2)
5711 elsif From_With_Type (T1)
5712 and then From_With_Type (T2)
5713 and then Available_View (T1) = Available_View (T2)
5720 end Matches_Limited_With_View;
5722 -- Start of processing for Conforming_Types
5725 -- The context is an instance association for a formal
5726 -- access-to-subprogram type; the formal parameter types require
5727 -- mapping because they may denote other formal parameters of the
5731 Type_1 := Get_Instance_Of (T1);
5732 Type_2 := Get_Instance_Of (T2);
5735 -- If one of the types is a view of the other introduced by a limited
5736 -- with clause, treat these as conforming for all purposes.
5738 if Matches_Limited_With_View (T1, T2) then
5741 elsif Base_Types_Match (Type_1, Type_2) then
5742 return Ctype <= Mode_Conformant
5743 or else Subtypes_Statically_Match (Type_1, Type_2);
5745 elsif Is_Incomplete_Or_Private_Type (Type_1)
5746 and then Present (Full_View (Type_1))
5747 and then Base_Types_Match (Full_View (Type_1), Type_2)
5749 return Ctype <= Mode_Conformant
5750 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
5752 elsif Ekind (Type_2) = E_Incomplete_Type
5753 and then Present (Full_View (Type_2))
5754 and then Base_Types_Match (Type_1, Full_View (Type_2))
5756 return Ctype <= Mode_Conformant
5757 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
5759 elsif Is_Private_Type (Type_2)
5760 and then In_Instance
5761 and then Present (Full_View (Type_2))
5762 and then Base_Types_Match (Type_1, Full_View (Type_2))
5764 return Ctype <= Mode_Conformant
5765 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
5768 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
5769 -- treated recursively because they carry a signature.
5771 Are_Anonymous_Access_To_Subprogram_Types :=
5772 Ekind (Type_1) = Ekind (Type_2)
5774 (Ekind (Type_1) = E_Anonymous_Access_Subprogram_Type
5776 Ekind (Type_1) = E_Anonymous_Access_Protected_Subprogram_Type);
5778 -- Test anonymous access type case. For this case, static subtype
5779 -- matching is required for mode conformance (RM 6.3.1(15)). We check
5780 -- the base types because we may have built internal subtype entities
5781 -- to handle null-excluding types (see Process_Formals).
5783 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
5785 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
5786 or else Are_Anonymous_Access_To_Subprogram_Types -- Ada 2005 (AI-254)
5789 Desig_1 : Entity_Id;
5790 Desig_2 : Entity_Id;
5793 -- In Ada2005, access constant indicators must match for
5794 -- subtype conformance.
5796 if Ada_Version >= Ada_2005
5797 and then Ctype >= Subtype_Conformant
5799 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
5804 Desig_1 := Find_Designated_Type (Type_1);
5805 Desig_2 := Find_Designated_Type (Type_2);
5807 -- If the context is an instance association for a formal
5808 -- access-to-subprogram type; formal access parameter designated
5809 -- types require mapping because they may denote other formal
5810 -- parameters of the generic unit.
5813 Desig_1 := Get_Instance_Of (Desig_1);
5814 Desig_2 := Get_Instance_Of (Desig_2);
5817 -- It is possible for a Class_Wide_Type to be introduced for an
5818 -- incomplete type, in which case there is a separate class_ wide
5819 -- type for the full view. The types conform if their Etypes
5820 -- conform, i.e. one may be the full view of the other. This can
5821 -- only happen in the context of an access parameter, other uses
5822 -- of an incomplete Class_Wide_Type are illegal.
5824 if Is_Class_Wide_Type (Desig_1)
5826 Is_Class_Wide_Type (Desig_2)
5830 (Etype (Base_Type (Desig_1)),
5831 Etype (Base_Type (Desig_2)), Ctype);
5833 elsif Are_Anonymous_Access_To_Subprogram_Types then
5834 if Ada_Version < Ada_2005 then
5835 return Ctype = Type_Conformant
5837 Subtypes_Statically_Match (Desig_1, Desig_2);
5839 -- We must check the conformance of the signatures themselves
5843 Conformant : Boolean;
5846 (Desig_1, Desig_2, Ctype, False, Conformant);
5852 return Base_Type (Desig_1) = Base_Type (Desig_2)
5853 and then (Ctype = Type_Conformant
5855 Subtypes_Statically_Match (Desig_1, Desig_2));
5859 -- Otherwise definitely no match
5862 if ((Ekind (Type_1) = E_Anonymous_Access_Type
5863 and then Is_Access_Type (Type_2))
5864 or else (Ekind (Type_2) = E_Anonymous_Access_Type
5865 and then Is_Access_Type (Type_1)))
5868 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
5870 May_Hide_Profile := True;
5875 end Conforming_Types;
5877 --------------------------
5878 -- Create_Extra_Formals --
5879 --------------------------
5881 procedure Create_Extra_Formals (E : Entity_Id) is
5883 First_Extra : Entity_Id := Empty;
5884 Last_Extra : Entity_Id;
5885 Formal_Type : Entity_Id;
5886 P_Formal : Entity_Id := Empty;
5888 function Add_Extra_Formal
5889 (Assoc_Entity : Entity_Id;
5892 Suffix : String) return Entity_Id;
5893 -- Add an extra formal to the current list of formals and extra formals.
5894 -- The extra formal is added to the end of the list of extra formals,
5895 -- and also returned as the result. These formals are always of mode IN.
5896 -- The new formal has the type Typ, is declared in Scope, and its name
5897 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
5898 -- The following suffixes are currently used. They should not be changed
5899 -- without coordinating with CodePeer, which makes use of these to
5900 -- provide better messages.
5902 -- O denotes the Constrained bit.
5903 -- L denotes the accessibility level.
5904 -- BIP_xxx denotes an extra formal for a build-in-place function. See
5905 -- the full list in exp_ch6.BIP_Formal_Kind.
5907 ----------------------
5908 -- Add_Extra_Formal --
5909 ----------------------
5911 function Add_Extra_Formal
5912 (Assoc_Entity : Entity_Id;
5915 Suffix : String) return Entity_Id
5917 EF : constant Entity_Id :=
5918 Make_Defining_Identifier (Sloc (Assoc_Entity),
5919 Chars => New_External_Name (Chars (Assoc_Entity),
5923 -- A little optimization. Never generate an extra formal for the
5924 -- _init operand of an initialization procedure, since it could
5927 if Chars (Formal) = Name_uInit then
5931 Set_Ekind (EF, E_In_Parameter);
5932 Set_Actual_Subtype (EF, Typ);
5933 Set_Etype (EF, Typ);
5934 Set_Scope (EF, Scope);
5935 Set_Mechanism (EF, Default_Mechanism);
5936 Set_Formal_Validity (EF);
5938 if No (First_Extra) then
5940 Set_Extra_Formals (Scope, First_Extra);
5943 if Present (Last_Extra) then
5944 Set_Extra_Formal (Last_Extra, EF);
5950 end Add_Extra_Formal;
5952 -- Start of processing for Create_Extra_Formals
5955 -- We never generate extra formals if expansion is not active
5956 -- because we don't need them unless we are generating code.
5958 if not Expander_Active then
5962 -- If this is a derived subprogram then the subtypes of the parent
5963 -- subprogram's formal parameters will be used to determine the need
5964 -- for extra formals.
5966 if Is_Overloadable (E) and then Present (Alias (E)) then
5967 P_Formal := First_Formal (Alias (E));
5970 Last_Extra := Empty;
5971 Formal := First_Formal (E);
5972 while Present (Formal) loop
5973 Last_Extra := Formal;
5974 Next_Formal (Formal);
5977 -- If Extra_formals were already created, don't do it again. This
5978 -- situation may arise for subprogram types created as part of
5979 -- dispatching calls (see Expand_Dispatching_Call)
5981 if Present (Last_Extra) and then
5982 Present (Extra_Formal (Last_Extra))
5987 -- If the subprogram is a predefined dispatching subprogram then don't
5988 -- generate any extra constrained or accessibility level formals. In
5989 -- general we suppress these for internal subprograms (by not calling
5990 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
5991 -- generated stream attributes do get passed through because extra
5992 -- build-in-place formals are needed in some cases (limited 'Input).
5994 if Is_Predefined_Internal_Operation (E) then
5995 goto Test_For_BIP_Extras;
5998 Formal := First_Formal (E);
5999 while Present (Formal) loop
6001 -- Create extra formal for supporting the attribute 'Constrained.
6002 -- The case of a private type view without discriminants also
6003 -- requires the extra formal if the underlying type has defaulted
6006 if Ekind (Formal) /= E_In_Parameter then
6007 if Present (P_Formal) then
6008 Formal_Type := Etype (P_Formal);
6010 Formal_Type := Etype (Formal);
6013 -- Do not produce extra formals for Unchecked_Union parameters.
6014 -- Jump directly to the end of the loop.
6016 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
6017 goto Skip_Extra_Formal_Generation;
6020 if not Has_Discriminants (Formal_Type)
6021 and then Ekind (Formal_Type) in Private_Kind
6022 and then Present (Underlying_Type (Formal_Type))
6024 Formal_Type := Underlying_Type (Formal_Type);
6027 -- Suppress the extra formal if formal's subtype is constrained or
6028 -- indefinite, or we're compiling for Ada 2012 and the underlying
6029 -- type is tagged and limited. In Ada 2012, a limited tagged type
6030 -- can have defaulted discriminants, but 'Constrained is required
6031 -- to return True, so the formal is never needed (see AI05-0214).
6032 -- Note that this ensures consistency of calling sequences for
6033 -- dispatching operations when some types in a class have defaults
6034 -- on discriminants and others do not (and requiring the extra
6035 -- formal would introduce distributed overhead).
6037 if Has_Discriminants (Formal_Type)
6038 and then not Is_Constrained (Formal_Type)
6039 and then not Is_Indefinite_Subtype (Formal_Type)
6040 and then (Ada_Version < Ada_2012
6042 not (Is_Tagged_Type (Underlying_Type (Formal_Type))
6043 and then Is_Limited_Type (Formal_Type)))
6045 Set_Extra_Constrained
6046 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
6050 -- Create extra formal for supporting accessibility checking. This
6051 -- is done for both anonymous access formals and formals of named
6052 -- access types that are marked as controlling formals. The latter
6053 -- case can occur when Expand_Dispatching_Call creates a subprogram
6054 -- type and substitutes the types of access-to-class-wide actuals
6055 -- for the anonymous access-to-specific-type of controlling formals.
6056 -- Base_Type is applied because in cases where there is a null
6057 -- exclusion the formal may have an access subtype.
6059 -- This is suppressed if we specifically suppress accessibility
6060 -- checks at the package level for either the subprogram, or the
6061 -- package in which it resides. However, we do not suppress it
6062 -- simply if the scope has accessibility checks suppressed, since
6063 -- this could cause trouble when clients are compiled with a
6064 -- different suppression setting. The explicit checks at the
6065 -- package level are safe from this point of view.
6067 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
6068 or else (Is_Controlling_Formal (Formal)
6069 and then Is_Access_Type (Base_Type (Etype (Formal)))))
6071 (Explicit_Suppress (E, Accessibility_Check)
6073 Explicit_Suppress (Scope (E), Accessibility_Check))
6076 or else Present (Extra_Accessibility (P_Formal)))
6078 Set_Extra_Accessibility
6079 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
6082 -- This label is required when skipping extra formal generation for
6083 -- Unchecked_Union parameters.
6085 <<Skip_Extra_Formal_Generation>>
6087 if Present (P_Formal) then
6088 Next_Formal (P_Formal);
6091 Next_Formal (Formal);
6094 <<Test_For_BIP_Extras>>
6096 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
6097 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
6099 if Ada_Version >= Ada_2005 and then Is_Build_In_Place_Function (E) then
6101 Result_Subt : constant Entity_Id := Etype (E);
6103 Discard : Entity_Id;
6104 pragma Warnings (Off, Discard);
6107 -- In the case of functions with unconstrained result subtypes,
6108 -- add a 4-state formal indicating whether the return object is
6109 -- allocated by the caller (1), or should be allocated by the
6110 -- callee on the secondary stack (2), in the global heap (3), or
6111 -- in a user-defined storage pool (4). For the moment we just use
6112 -- Natural for the type of this formal. Note that this formal
6113 -- isn't usually needed in the case where the result subtype is
6114 -- constrained, but it is needed when the function has a tagged
6115 -- result, because generally such functions can be called in a
6116 -- dispatching context and such calls must be handled like calls
6117 -- to a class-wide function.
6119 if not Is_Constrained (Underlying_Type (Result_Subt))
6120 or else Is_Tagged_Type (Underlying_Type (Result_Subt))
6124 (E, Standard_Natural,
6125 E, BIP_Formal_Suffix (BIP_Alloc_Form));
6128 -- In the case of functions whose result type needs finalization,
6129 -- add an extra formal which represents the finalization master.
6131 if Needs_BIP_Finalization_Master (E) then
6134 (E, RTE (RE_Finalization_Master_Ptr),
6135 E, BIP_Formal_Suffix (BIP_Finalization_Master));
6138 -- If the result type contains tasks, we have two extra formals:
6139 -- the master of the tasks to be created, and the caller's
6140 -- activation chain.
6142 if Has_Task (Result_Subt) then
6145 (E, RTE (RE_Master_Id),
6146 E, BIP_Formal_Suffix (BIP_Master));
6149 (E, RTE (RE_Activation_Chain_Access),
6150 E, BIP_Formal_Suffix (BIP_Activation_Chain));
6153 -- All build-in-place functions get an extra formal that will be
6154 -- passed the address of the return object within the caller.
6157 Formal_Type : constant Entity_Id :=
6159 (E_Anonymous_Access_Type, E,
6160 Scope_Id => Scope (E));
6162 Set_Directly_Designated_Type (Formal_Type, Result_Subt);
6163 Set_Etype (Formal_Type, Formal_Type);
6164 Set_Depends_On_Private
6165 (Formal_Type, Has_Private_Component (Formal_Type));
6166 Set_Is_Public (Formal_Type, Is_Public (Scope (Formal_Type)));
6167 Set_Is_Access_Constant (Formal_Type, False);
6169 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
6170 -- the designated type comes from the limited view (for
6171 -- back-end purposes).
6173 Set_From_With_Type (Formal_Type, From_With_Type (Result_Subt));
6175 Layout_Type (Formal_Type);
6179 (E, Formal_Type, E, BIP_Formal_Suffix (BIP_Object_Access));
6183 end Create_Extra_Formals;
6185 -----------------------------
6186 -- Enter_Overloaded_Entity --
6187 -----------------------------
6189 procedure Enter_Overloaded_Entity (S : Entity_Id) is
6190 E : Entity_Id := Current_Entity_In_Scope (S);
6191 C_E : Entity_Id := Current_Entity (S);
6195 Set_Has_Homonym (E);
6196 Set_Has_Homonym (S);
6199 Set_Is_Immediately_Visible (S);
6200 Set_Scope (S, Current_Scope);
6202 -- Chain new entity if front of homonym in current scope, so that
6203 -- homonyms are contiguous.
6208 while Homonym (C_E) /= E loop
6209 C_E := Homonym (C_E);
6212 Set_Homonym (C_E, S);
6216 Set_Current_Entity (S);
6221 Append_Entity (S, Current_Scope);
6222 Set_Public_Status (S);
6224 if Debug_Flag_E then
6225 Write_Str ("New overloaded entity chain: ");
6226 Write_Name (Chars (S));
6229 while Present (E) loop
6230 Write_Str (" "); Write_Int (Int (E));
6237 -- Generate warning for hiding
6240 and then Comes_From_Source (S)
6241 and then In_Extended_Main_Source_Unit (S)
6248 -- Warn unless genuine overloading. Do not emit warning on
6249 -- hiding predefined operators in Standard (these are either an
6250 -- (artifact of our implicit declarations, or simple noise) but
6251 -- keep warning on a operator defined on a local subtype, because
6252 -- of the real danger that different operators may be applied in
6253 -- various parts of the program.
6255 -- Note that if E and S have the same scope, there is never any
6256 -- hiding. Either the two conflict, and the program is illegal,
6257 -- or S is overriding an implicit inherited subprogram.
6259 if Scope (E) /= Scope (S)
6260 and then (not Is_Overloadable (E)
6261 or else Subtype_Conformant (E, S))
6262 and then (Is_Immediately_Visible (E)
6264 Is_Potentially_Use_Visible (S))
6266 if Scope (E) /= Standard_Standard then
6267 Error_Msg_Sloc := Sloc (E);
6268 Error_Msg_N ("declaration of & hides one#?", S);
6270 elsif Nkind (S) = N_Defining_Operator_Symbol
6272 Scope (Base_Type (Etype (First_Formal (S)))) /= Scope (S)
6275 ("declaration of & hides predefined operator?", S);
6280 end Enter_Overloaded_Entity;
6282 -----------------------------
6283 -- Check_Untagged_Equality --
6284 -----------------------------
6286 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
6287 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
6288 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
6292 if Nkind (Decl) = N_Subprogram_Declaration
6293 and then Is_Record_Type (Typ)
6294 and then not Is_Tagged_Type (Typ)
6296 -- If the type is not declared in a package, or if we are in the
6297 -- body of the package or in some other scope, the new operation is
6298 -- not primitive, and therefore legal, though suspicious. If the
6299 -- type is a generic actual (sub)type, the operation is not primitive
6300 -- either because the base type is declared elsewhere.
6302 if Is_Frozen (Typ) then
6303 if Ekind (Scope (Typ)) /= E_Package
6304 or else Scope (Typ) /= Current_Scope
6308 elsif Is_Generic_Actual_Type (Typ) then
6311 elsif In_Package_Body (Scope (Typ)) then
6313 ("equality operator must be declared "
6314 & "before type& is frozen", Eq_Op, Typ);
6316 ("\move declaration to package spec", Eq_Op);
6320 ("equality operator must be declared "
6321 & "before type& is frozen", Eq_Op, Typ);
6323 Obj_Decl := Next (Parent (Typ));
6324 while Present (Obj_Decl)
6325 and then Obj_Decl /= Decl
6327 if Nkind (Obj_Decl) = N_Object_Declaration
6328 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
6330 Error_Msg_NE ("type& is frozen by declaration?",
6333 ("\an equality operator cannot be declared after this "
6334 & "point (RM 4.5.2 (9.8)) (Ada 2012))?", Obj_Decl);
6342 elsif not In_Same_List (Parent (Typ), Decl)
6343 and then not Is_Limited_Type (Typ)
6346 -- This makes it illegal to have a primitive equality declared in
6347 -- the private part if the type is visible.
6349 Error_Msg_N ("equality operator appears too late", Eq_Op);
6352 end Check_Untagged_Equality;
6354 -----------------------------
6355 -- Find_Corresponding_Spec --
6356 -----------------------------
6358 function Find_Corresponding_Spec
6360 Post_Error : Boolean := True) return Entity_Id
6362 Spec : constant Node_Id := Specification (N);
6363 Designator : constant Entity_Id := Defining_Entity (Spec);
6368 E := Current_Entity (Designator);
6369 while Present (E) loop
6371 -- We are looking for a matching spec. It must have the same scope,
6372 -- and the same name, and either be type conformant, or be the case
6373 -- of a library procedure spec and its body (which belong to one
6374 -- another regardless of whether they are type conformant or not).
6376 if Scope (E) = Current_Scope then
6377 if Current_Scope = Standard_Standard
6378 or else (Ekind (E) = Ekind (Designator)
6379 and then Type_Conformant (E, Designator))
6381 -- Within an instantiation, we know that spec and body are
6382 -- subtype conformant, because they were subtype conformant
6383 -- in the generic. We choose the subtype-conformant entity
6384 -- here as well, to resolve spurious ambiguities in the
6385 -- instance that were not present in the generic (i.e. when
6386 -- two different types are given the same actual). If we are
6387 -- looking for a spec to match a body, full conformance is
6391 Set_Convention (Designator, Convention (E));
6393 -- Skip past subprogram bodies and subprogram renamings that
6394 -- may appear to have a matching spec, but that aren't fully
6395 -- conformant with it. That can occur in cases where an
6396 -- actual type causes unrelated homographs in the instance.
6398 if Nkind_In (N, N_Subprogram_Body,
6399 N_Subprogram_Renaming_Declaration)
6400 and then Present (Homonym (E))
6401 and then not Fully_Conformant (Designator, E)
6405 elsif not Subtype_Conformant (Designator, E) then
6410 -- Ada 2012 (AI05-0165): For internally generated bodies of
6411 -- null procedures locate the internally generated spec. We
6412 -- enforce mode conformance since a tagged type may inherit
6413 -- from interfaces several null primitives which differ only
6414 -- in the mode of the formals.
6416 if not (Comes_From_Source (E))
6417 and then Is_Null_Procedure (E)
6418 and then not Mode_Conformant (Designator, E)
6422 elsif not Has_Completion (E) then
6423 if Nkind (N) /= N_Subprogram_Body_Stub then
6424 Set_Corresponding_Spec (N, E);
6427 Set_Has_Completion (E);
6430 elsif Nkind (Parent (N)) = N_Subunit then
6432 -- If this is the proper body of a subunit, the completion
6433 -- flag is set when analyzing the stub.
6437 -- If E is an internal function with a controlling result
6438 -- that was created for an operation inherited by a null
6439 -- extension, it may be overridden by a body without a previous
6440 -- spec (one more reason why these should be shunned). In that
6441 -- case remove the generated body if present, because the
6442 -- current one is the explicit overriding.
6444 elsif Ekind (E) = E_Function
6445 and then Ada_Version >= Ada_2005
6446 and then not Comes_From_Source (E)
6447 and then Has_Controlling_Result (E)
6448 and then Is_Null_Extension (Etype (E))
6449 and then Comes_From_Source (Spec)
6451 Set_Has_Completion (E, False);
6454 and then Nkind (Parent (E)) = N_Function_Specification
6457 (Unit_Declaration_Node
6458 (Corresponding_Body (Unit_Declaration_Node (E))));
6462 -- If expansion is disabled, or if the wrapper function has
6463 -- not been generated yet, this a late body overriding an
6464 -- inherited operation, or it is an overriding by some other
6465 -- declaration before the controlling result is frozen. In
6466 -- either case this is a declaration of a new entity.
6472 -- If the body already exists, then this is an error unless
6473 -- the previous declaration is the implicit declaration of a
6474 -- derived subprogram. It is also legal for an instance to
6475 -- contain type conformant overloadable declarations (but the
6476 -- generic declaration may not), per 8.3(26/2).
6478 elsif No (Alias (E))
6479 and then not Is_Intrinsic_Subprogram (E)
6480 and then not In_Instance
6483 Error_Msg_Sloc := Sloc (E);
6485 if Is_Imported (E) then
6487 ("body not allowed for imported subprogram & declared#",
6490 Error_Msg_NE ("duplicate body for & declared#", N, E);
6494 -- Child units cannot be overloaded, so a conformance mismatch
6495 -- between body and a previous spec is an error.
6497 elsif Is_Child_Unit (E)
6499 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
6501 Nkind (Parent (Unit_Declaration_Node (Designator))) =
6506 ("body of child unit does not match previous declaration", N);
6514 -- On exit, we know that no previous declaration of subprogram exists
6517 end Find_Corresponding_Spec;
6519 ----------------------
6520 -- Fully_Conformant --
6521 ----------------------
6523 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
6526 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
6528 end Fully_Conformant;
6530 ----------------------------------
6531 -- Fully_Conformant_Expressions --
6532 ----------------------------------
6534 function Fully_Conformant_Expressions
6535 (Given_E1 : Node_Id;
6536 Given_E2 : Node_Id) return Boolean
6538 E1 : constant Node_Id := Original_Node (Given_E1);
6539 E2 : constant Node_Id := Original_Node (Given_E2);
6540 -- We always test conformance on original nodes, since it is possible
6541 -- for analysis and/or expansion to make things look as though they
6542 -- conform when they do not, e.g. by converting 1+2 into 3.
6544 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
6545 renames Fully_Conformant_Expressions;
6547 function FCL (L1, L2 : List_Id) return Boolean;
6548 -- Compare elements of two lists for conformance. Elements have to
6549 -- be conformant, and actuals inserted as default parameters do not
6550 -- match explicit actuals with the same value.
6552 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
6553 -- Compare an operator node with a function call
6559 function FCL (L1, L2 : List_Id) return Boolean is
6563 if L1 = No_List then
6569 if L2 = No_List then
6575 -- Compare two lists, skipping rewrite insertions (we want to
6576 -- compare the original trees, not the expanded versions!)
6579 if Is_Rewrite_Insertion (N1) then
6581 elsif Is_Rewrite_Insertion (N2) then
6587 elsif not FCE (N1, N2) then
6600 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
6601 Actuals : constant List_Id := Parameter_Associations (Call_Node);
6606 or else Entity (Op_Node) /= Entity (Name (Call_Node))
6611 Act := First (Actuals);
6613 if Nkind (Op_Node) in N_Binary_Op then
6614 if not FCE (Left_Opnd (Op_Node), Act) then
6621 return Present (Act)
6622 and then FCE (Right_Opnd (Op_Node), Act)
6623 and then No (Next (Act));
6627 -- Start of processing for Fully_Conformant_Expressions
6630 -- Non-conformant if paren count does not match. Note: if some idiot
6631 -- complains that we don't do this right for more than 3 levels of
6632 -- parentheses, they will be treated with the respect they deserve!
6634 if Paren_Count (E1) /= Paren_Count (E2) then
6637 -- If same entities are referenced, then they are conformant even if
6638 -- they have different forms (RM 8.3.1(19-20)).
6640 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
6641 if Present (Entity (E1)) then
6642 return Entity (E1) = Entity (E2)
6643 or else (Chars (Entity (E1)) = Chars (Entity (E2))
6644 and then Ekind (Entity (E1)) = E_Discriminant
6645 and then Ekind (Entity (E2)) = E_In_Parameter);
6647 elsif Nkind (E1) = N_Expanded_Name
6648 and then Nkind (E2) = N_Expanded_Name
6649 and then Nkind (Selector_Name (E1)) = N_Character_Literal
6650 and then Nkind (Selector_Name (E2)) = N_Character_Literal
6652 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
6655 -- Identifiers in component associations don't always have
6656 -- entities, but their names must conform.
6658 return Nkind (E1) = N_Identifier
6659 and then Nkind (E2) = N_Identifier
6660 and then Chars (E1) = Chars (E2);
6663 elsif Nkind (E1) = N_Character_Literal
6664 and then Nkind (E2) = N_Expanded_Name
6666 return Nkind (Selector_Name (E2)) = N_Character_Literal
6667 and then Chars (E1) = Chars (Selector_Name (E2));
6669 elsif Nkind (E2) = N_Character_Literal
6670 and then Nkind (E1) = N_Expanded_Name
6672 return Nkind (Selector_Name (E1)) = N_Character_Literal
6673 and then Chars (E2) = Chars (Selector_Name (E1));
6675 elsif Nkind (E1) in N_Op
6676 and then Nkind (E2) = N_Function_Call
6678 return FCO (E1, E2);
6680 elsif Nkind (E2) in N_Op
6681 and then Nkind (E1) = N_Function_Call
6683 return FCO (E2, E1);
6685 -- Otherwise we must have the same syntactic entity
6687 elsif Nkind (E1) /= Nkind (E2) then
6690 -- At this point, we specialize by node type
6697 FCL (Expressions (E1), Expressions (E2))
6699 FCL (Component_Associations (E1),
6700 Component_Associations (E2));
6703 if Nkind (Expression (E1)) = N_Qualified_Expression
6705 Nkind (Expression (E2)) = N_Qualified_Expression
6707 return FCE (Expression (E1), Expression (E2));
6709 -- Check that the subtype marks and any constraints
6714 Indic1 : constant Node_Id := Expression (E1);
6715 Indic2 : constant Node_Id := Expression (E2);
6720 if Nkind (Indic1) /= N_Subtype_Indication then
6722 Nkind (Indic2) /= N_Subtype_Indication
6723 and then Entity (Indic1) = Entity (Indic2);
6725 elsif Nkind (Indic2) /= N_Subtype_Indication then
6727 Nkind (Indic1) /= N_Subtype_Indication
6728 and then Entity (Indic1) = Entity (Indic2);
6731 if Entity (Subtype_Mark (Indic1)) /=
6732 Entity (Subtype_Mark (Indic2))
6737 Elt1 := First (Constraints (Constraint (Indic1)));
6738 Elt2 := First (Constraints (Constraint (Indic2)));
6739 while Present (Elt1) and then Present (Elt2) loop
6740 if not FCE (Elt1, Elt2) then
6753 when N_Attribute_Reference =>
6755 Attribute_Name (E1) = Attribute_Name (E2)
6756 and then FCL (Expressions (E1), Expressions (E2));
6760 Entity (E1) = Entity (E2)
6761 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
6762 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
6764 when N_Short_Circuit | N_Membership_Test =>
6766 FCE (Left_Opnd (E1), Left_Opnd (E2))
6768 FCE (Right_Opnd (E1), Right_Opnd (E2));
6770 when N_Case_Expression =>
6776 if not FCE (Expression (E1), Expression (E2)) then
6780 Alt1 := First (Alternatives (E1));
6781 Alt2 := First (Alternatives (E2));
6783 if Present (Alt1) /= Present (Alt2) then
6785 elsif No (Alt1) then
6789 if not FCE (Expression (Alt1), Expression (Alt2))
6790 or else not FCL (Discrete_Choices (Alt1),
6791 Discrete_Choices (Alt2))
6802 when N_Character_Literal =>
6804 Char_Literal_Value (E1) = Char_Literal_Value (E2);
6806 when N_Component_Association =>
6808 FCL (Choices (E1), Choices (E2))
6810 FCE (Expression (E1), Expression (E2));
6812 when N_Conditional_Expression =>
6814 FCL (Expressions (E1), Expressions (E2));
6816 when N_Explicit_Dereference =>
6818 FCE (Prefix (E1), Prefix (E2));
6820 when N_Extension_Aggregate =>
6822 FCL (Expressions (E1), Expressions (E2))
6823 and then Null_Record_Present (E1) =
6824 Null_Record_Present (E2)
6825 and then FCL (Component_Associations (E1),
6826 Component_Associations (E2));
6828 when N_Function_Call =>
6830 FCE (Name (E1), Name (E2))
6832 FCL (Parameter_Associations (E1),
6833 Parameter_Associations (E2));
6835 when N_Indexed_Component =>
6837 FCE (Prefix (E1), Prefix (E2))
6839 FCL (Expressions (E1), Expressions (E2));
6841 when N_Integer_Literal =>
6842 return (Intval (E1) = Intval (E2));
6847 when N_Operator_Symbol =>
6849 Chars (E1) = Chars (E2);
6851 when N_Others_Choice =>
6854 when N_Parameter_Association =>
6856 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
6857 and then FCE (Explicit_Actual_Parameter (E1),
6858 Explicit_Actual_Parameter (E2));
6860 when N_Qualified_Expression =>
6862 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
6864 FCE (Expression (E1), Expression (E2));
6866 when N_Quantified_Expression =>
6867 if not FCE (Condition (E1), Condition (E2)) then
6871 if Present (Loop_Parameter_Specification (E1))
6872 and then Present (Loop_Parameter_Specification (E2))
6875 L1 : constant Node_Id :=
6876 Loop_Parameter_Specification (E1);
6877 L2 : constant Node_Id :=
6878 Loop_Parameter_Specification (E2);
6882 Reverse_Present (L1) = Reverse_Present (L2)
6884 FCE (Defining_Identifier (L1),
6885 Defining_Identifier (L2))
6887 FCE (Discrete_Subtype_Definition (L1),
6888 Discrete_Subtype_Definition (L2));
6891 else -- quantified expression with an iterator
6893 I1 : constant Node_Id := Iterator_Specification (E1);
6894 I2 : constant Node_Id := Iterator_Specification (E2);
6898 FCE (Defining_Identifier (I1),
6899 Defining_Identifier (I2))
6901 Of_Present (I1) = Of_Present (I2)
6903 Reverse_Present (I1) = Reverse_Present (I2)
6904 and then FCE (Name (I1), Name (I2))
6905 and then FCE (Subtype_Indication (I1),
6906 Subtype_Indication (I2));
6912 FCE (Low_Bound (E1), Low_Bound (E2))
6914 FCE (High_Bound (E1), High_Bound (E2));
6916 when N_Real_Literal =>
6917 return (Realval (E1) = Realval (E2));
6919 when N_Selected_Component =>
6921 FCE (Prefix (E1), Prefix (E2))
6923 FCE (Selector_Name (E1), Selector_Name (E2));
6927 FCE (Prefix (E1), Prefix (E2))
6929 FCE (Discrete_Range (E1), Discrete_Range (E2));
6931 when N_String_Literal =>
6933 S1 : constant String_Id := Strval (E1);
6934 S2 : constant String_Id := Strval (E2);
6935 L1 : constant Nat := String_Length (S1);
6936 L2 : constant Nat := String_Length (S2);
6943 for J in 1 .. L1 loop
6944 if Get_String_Char (S1, J) /=
6945 Get_String_Char (S2, J)
6955 when N_Type_Conversion =>
6957 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
6959 FCE (Expression (E1), Expression (E2));
6963 Entity (E1) = Entity (E2)
6965 FCE (Right_Opnd (E1), Right_Opnd (E2));
6967 when N_Unchecked_Type_Conversion =>
6969 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
6971 FCE (Expression (E1), Expression (E2));
6973 -- All other node types cannot appear in this context. Strictly
6974 -- we should raise a fatal internal error. Instead we just ignore
6975 -- the nodes. This means that if anyone makes a mistake in the
6976 -- expander and mucks an expression tree irretrievably, the
6977 -- result will be a failure to detect a (probably very obscure)
6978 -- case of non-conformance, which is better than bombing on some
6979 -- case where two expressions do in fact conform.
6986 end Fully_Conformant_Expressions;
6988 ----------------------------------------
6989 -- Fully_Conformant_Discrete_Subtypes --
6990 ----------------------------------------
6992 function Fully_Conformant_Discrete_Subtypes
6993 (Given_S1 : Node_Id;
6994 Given_S2 : Node_Id) return Boolean
6996 S1 : constant Node_Id := Original_Node (Given_S1);
6997 S2 : constant Node_Id := Original_Node (Given_S2);
6999 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
7000 -- Special-case for a bound given by a discriminant, which in the body
7001 -- is replaced with the discriminal of the enclosing type.
7003 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
7004 -- Check both bounds
7006 -----------------------
7007 -- Conforming_Bounds --
7008 -----------------------
7010 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
7012 if Is_Entity_Name (B1)
7013 and then Is_Entity_Name (B2)
7014 and then Ekind (Entity (B1)) = E_Discriminant
7016 return Chars (B1) = Chars (B2);
7019 return Fully_Conformant_Expressions (B1, B2);
7021 end Conforming_Bounds;
7023 -----------------------
7024 -- Conforming_Ranges --
7025 -----------------------
7027 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
7030 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
7032 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
7033 end Conforming_Ranges;
7035 -- Start of processing for Fully_Conformant_Discrete_Subtypes
7038 if Nkind (S1) /= Nkind (S2) then
7041 elsif Is_Entity_Name (S1) then
7042 return Entity (S1) = Entity (S2);
7044 elsif Nkind (S1) = N_Range then
7045 return Conforming_Ranges (S1, S2);
7047 elsif Nkind (S1) = N_Subtype_Indication then
7049 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
7052 (Range_Expression (Constraint (S1)),
7053 Range_Expression (Constraint (S2)));
7057 end Fully_Conformant_Discrete_Subtypes;
7059 --------------------
7060 -- Install_Entity --
7061 --------------------
7063 procedure Install_Entity (E : Entity_Id) is
7064 Prev : constant Entity_Id := Current_Entity (E);
7066 Set_Is_Immediately_Visible (E);
7067 Set_Current_Entity (E);
7068 Set_Homonym (E, Prev);
7071 ---------------------
7072 -- Install_Formals --
7073 ---------------------
7075 procedure Install_Formals (Id : Entity_Id) is
7078 F := First_Formal (Id);
7079 while Present (F) loop
7083 end Install_Formals;
7085 -----------------------------
7086 -- Is_Interface_Conformant --
7087 -----------------------------
7089 function Is_Interface_Conformant
7090 (Tagged_Type : Entity_Id;
7091 Iface_Prim : Entity_Id;
7092 Prim : Entity_Id) return Boolean
7094 Iface : constant Entity_Id := Find_Dispatching_Type (Iface_Prim);
7095 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
7097 function Controlling_Formal (Prim : Entity_Id) return Entity_Id;
7098 -- Return the controlling formal of Prim
7100 ------------------------
7101 -- Controlling_Formal --
7102 ------------------------
7104 function Controlling_Formal (Prim : Entity_Id) return Entity_Id is
7105 E : Entity_Id := First_Entity (Prim);
7108 while Present (E) loop
7109 if Is_Formal (E) and then Is_Controlling_Formal (E) then
7117 end Controlling_Formal;
7121 Iface_Ctrl_F : constant Entity_Id := Controlling_Formal (Iface_Prim);
7122 Prim_Ctrl_F : constant Entity_Id := Controlling_Formal (Prim);
7124 -- Start of processing for Is_Interface_Conformant
7127 pragma Assert (Is_Subprogram (Iface_Prim)
7128 and then Is_Subprogram (Prim)
7129 and then Is_Dispatching_Operation (Iface_Prim)
7130 and then Is_Dispatching_Operation (Prim));
7132 pragma Assert (Is_Interface (Iface)
7133 or else (Present (Alias (Iface_Prim))
7136 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
7138 if Prim = Iface_Prim
7139 or else not Is_Subprogram (Prim)
7140 or else Ekind (Prim) /= Ekind (Iface_Prim)
7141 or else not Is_Dispatching_Operation (Prim)
7142 or else Scope (Prim) /= Scope (Tagged_Type)
7144 or else Base_Type (Typ) /= Tagged_Type
7145 or else not Primitive_Names_Match (Iface_Prim, Prim)
7149 -- The mode of the controlling formals must match
7151 elsif Present (Iface_Ctrl_F)
7152 and then Present (Prim_Ctrl_F)
7153 and then Ekind (Iface_Ctrl_F) /= Ekind (Prim_Ctrl_F)
7157 -- Case of a procedure, or a function whose result type matches the
7158 -- result type of the interface primitive, or a function that has no
7159 -- controlling result (I or access I).
7161 elsif Ekind (Iface_Prim) = E_Procedure
7162 or else Etype (Prim) = Etype (Iface_Prim)
7163 or else not Has_Controlling_Result (Prim)
7165 return Type_Conformant
7166 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
7168 -- Case of a function returning an interface, or an access to one.
7169 -- Check that the return types correspond.
7171 elsif Implements_Interface (Typ, Iface) then
7172 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
7174 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
7179 Type_Conformant (Prim, Iface_Prim,
7180 Skip_Controlling_Formals => True);
7186 end Is_Interface_Conformant;
7188 ---------------------------------
7189 -- Is_Non_Overriding_Operation --
7190 ---------------------------------
7192 function Is_Non_Overriding_Operation
7193 (Prev_E : Entity_Id;
7194 New_E : Entity_Id) return Boolean
7198 G_Typ : Entity_Id := Empty;
7200 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
7201 -- If F_Type is a derived type associated with a generic actual subtype,
7202 -- then return its Generic_Parent_Type attribute, else return Empty.
7204 function Types_Correspond
7205 (P_Type : Entity_Id;
7206 N_Type : Entity_Id) return Boolean;
7207 -- Returns true if and only if the types (or designated types in the
7208 -- case of anonymous access types) are the same or N_Type is derived
7209 -- directly or indirectly from P_Type.
7211 -----------------------------
7212 -- Get_Generic_Parent_Type --
7213 -----------------------------
7215 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
7221 if Is_Derived_Type (F_Typ)
7222 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
7224 -- The tree must be traversed to determine the parent subtype in
7225 -- the generic unit, which unfortunately isn't always available
7226 -- via semantic attributes. ??? (Note: The use of Original_Node
7227 -- is needed for cases where a full derived type has been
7230 Defn := Type_Definition (Original_Node (Parent (F_Typ)));
7231 if Nkind (Defn) = N_Derived_Type_Definition then
7232 Indic := Subtype_Indication (Defn);
7234 if Nkind (Indic) = N_Subtype_Indication then
7235 G_Typ := Entity (Subtype_Mark (Indic));
7237 G_Typ := Entity (Indic);
7240 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
7241 and then Present (Generic_Parent_Type (Parent (G_Typ)))
7243 return Generic_Parent_Type (Parent (G_Typ));
7249 end Get_Generic_Parent_Type;
7251 ----------------------
7252 -- Types_Correspond --
7253 ----------------------
7255 function Types_Correspond
7256 (P_Type : Entity_Id;
7257 N_Type : Entity_Id) return Boolean
7259 Prev_Type : Entity_Id := Base_Type (P_Type);
7260 New_Type : Entity_Id := Base_Type (N_Type);
7263 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
7264 Prev_Type := Designated_Type (Prev_Type);
7267 if Ekind (New_Type) = E_Anonymous_Access_Type then
7268 New_Type := Designated_Type (New_Type);
7271 if Prev_Type = New_Type then
7274 elsif not Is_Class_Wide_Type (New_Type) then
7275 while Etype (New_Type) /= New_Type loop
7276 New_Type := Etype (New_Type);
7277 if New_Type = Prev_Type then
7283 end Types_Correspond;
7285 -- Start of processing for Is_Non_Overriding_Operation
7288 -- In the case where both operations are implicit derived subprograms
7289 -- then neither overrides the other. This can only occur in certain
7290 -- obscure cases (e.g., derivation from homographs created in a generic
7293 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
7296 elsif Ekind (Current_Scope) = E_Package
7297 and then Is_Generic_Instance (Current_Scope)
7298 and then In_Private_Part (Current_Scope)
7299 and then Comes_From_Source (New_E)
7301 -- We examine the formals and result type of the inherited operation,
7302 -- to determine whether their type is derived from (the instance of)
7303 -- a generic type. The first such formal or result type is the one
7306 Formal := First_Formal (Prev_E);
7307 while Present (Formal) loop
7308 F_Typ := Base_Type (Etype (Formal));
7310 if Ekind (F_Typ) = E_Anonymous_Access_Type then
7311 F_Typ := Designated_Type (F_Typ);
7314 G_Typ := Get_Generic_Parent_Type (F_Typ);
7315 exit when Present (G_Typ);
7317 Next_Formal (Formal);
7320 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
7321 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
7328 -- If the generic type is a private type, then the original operation
7329 -- was not overriding in the generic, because there was no primitive
7330 -- operation to override.
7332 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
7333 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
7334 N_Formal_Private_Type_Definition
7338 -- The generic parent type is the ancestor of a formal derived
7339 -- type declaration. We need to check whether it has a primitive
7340 -- operation that should be overridden by New_E in the generic.
7344 P_Formal : Entity_Id;
7345 N_Formal : Entity_Id;
7349 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
7352 while Present (Prim_Elt) loop
7353 P_Prim := Node (Prim_Elt);
7355 if Chars (P_Prim) = Chars (New_E)
7356 and then Ekind (P_Prim) = Ekind (New_E)
7358 P_Formal := First_Formal (P_Prim);
7359 N_Formal := First_Formal (New_E);
7360 while Present (P_Formal) and then Present (N_Formal) loop
7361 P_Typ := Etype (P_Formal);
7362 N_Typ := Etype (N_Formal);
7364 if not Types_Correspond (P_Typ, N_Typ) then
7368 Next_Entity (P_Formal);
7369 Next_Entity (N_Formal);
7372 -- Found a matching primitive operation belonging to the
7373 -- formal ancestor type, so the new subprogram is
7377 and then No (N_Formal)
7378 and then (Ekind (New_E) /= E_Function
7381 (Etype (P_Prim), Etype (New_E)))
7387 Next_Elmt (Prim_Elt);
7390 -- If no match found, then the new subprogram does not
7391 -- override in the generic (nor in the instance).
7399 end Is_Non_Overriding_Operation;
7401 -------------------------------------
7402 -- List_Inherited_Pre_Post_Aspects --
7403 -------------------------------------
7405 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
7407 if Opt.List_Inherited_Aspects
7408 and then (Is_Subprogram (E) or else Is_Generic_Subprogram (E))
7411 Inherited : constant Subprogram_List :=
7412 Inherited_Subprograms (E);
7416 for J in Inherited'Range loop
7417 P := Spec_PPC_List (Contract (Inherited (J)));
7419 while Present (P) loop
7420 Error_Msg_Sloc := Sloc (P);
7422 if Class_Present (P) and then not Split_PPC (P) then
7423 if Pragma_Name (P) = Name_Precondition then
7425 ("?info: & inherits `Pre''Class` aspect from #", E);
7428 ("?info: & inherits `Post''Class` aspect from #", E);
7432 P := Next_Pragma (P);
7437 end List_Inherited_Pre_Post_Aspects;
7439 ------------------------------
7440 -- Make_Inequality_Operator --
7441 ------------------------------
7443 -- S is the defining identifier of an equality operator. We build a
7444 -- subprogram declaration with the right signature. This operation is
7445 -- intrinsic, because it is always expanded as the negation of the
7446 -- call to the equality function.
7448 procedure Make_Inequality_Operator (S : Entity_Id) is
7449 Loc : constant Source_Ptr := Sloc (S);
7452 Op_Name : Entity_Id;
7454 FF : constant Entity_Id := First_Formal (S);
7455 NF : constant Entity_Id := Next_Formal (FF);
7458 -- Check that equality was properly defined, ignore call if not
7465 A : constant Entity_Id :=
7466 Make_Defining_Identifier (Sloc (FF),
7467 Chars => Chars (FF));
7469 B : constant Entity_Id :=
7470 Make_Defining_Identifier (Sloc (NF),
7471 Chars => Chars (NF));
7474 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
7476 Formals := New_List (
7477 Make_Parameter_Specification (Loc,
7478 Defining_Identifier => A,
7480 New_Reference_To (Etype (First_Formal (S)),
7481 Sloc (Etype (First_Formal (S))))),
7483 Make_Parameter_Specification (Loc,
7484 Defining_Identifier => B,
7486 New_Reference_To (Etype (Next_Formal (First_Formal (S))),
7487 Sloc (Etype (Next_Formal (First_Formal (S)))))));
7490 Make_Subprogram_Declaration (Loc,
7492 Make_Function_Specification (Loc,
7493 Defining_Unit_Name => Op_Name,
7494 Parameter_Specifications => Formals,
7495 Result_Definition =>
7496 New_Reference_To (Standard_Boolean, Loc)));
7498 -- Insert inequality right after equality if it is explicit or after
7499 -- the derived type when implicit. These entities are created only
7500 -- for visibility purposes, and eventually replaced in the course of
7501 -- expansion, so they do not need to be attached to the tree and seen
7502 -- by the back-end. Keeping them internal also avoids spurious
7503 -- freezing problems. The declaration is inserted in the tree for
7504 -- analysis, and removed afterwards. If the equality operator comes
7505 -- from an explicit declaration, attach the inequality immediately
7506 -- after. Else the equality is inherited from a derived type
7507 -- declaration, so insert inequality after that declaration.
7509 if No (Alias (S)) then
7510 Insert_After (Unit_Declaration_Node (S), Decl);
7511 elsif Is_List_Member (Parent (S)) then
7512 Insert_After (Parent (S), Decl);
7514 Insert_After (Parent (Etype (First_Formal (S))), Decl);
7517 Mark_Rewrite_Insertion (Decl);
7518 Set_Is_Intrinsic_Subprogram (Op_Name);
7521 Set_Has_Completion (Op_Name);
7522 Set_Corresponding_Equality (Op_Name, S);
7523 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
7525 end Make_Inequality_Operator;
7527 ----------------------
7528 -- May_Need_Actuals --
7529 ----------------------
7531 procedure May_Need_Actuals (Fun : Entity_Id) is
7536 F := First_Formal (Fun);
7538 while Present (F) loop
7539 if No (Default_Value (F)) then
7547 Set_Needs_No_Actuals (Fun, B);
7548 end May_Need_Actuals;
7550 ---------------------
7551 -- Mode_Conformant --
7552 ---------------------
7554 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
7557 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
7559 end Mode_Conformant;
7561 ---------------------------
7562 -- New_Overloaded_Entity --
7563 ---------------------------
7565 procedure New_Overloaded_Entity
7567 Derived_Type : Entity_Id := Empty)
7569 Overridden_Subp : Entity_Id := Empty;
7570 -- Set if the current scope has an operation that is type-conformant
7571 -- with S, and becomes hidden by S.
7573 Is_Primitive_Subp : Boolean;
7574 -- Set to True if the new subprogram is primitive
7577 -- Entity that S overrides
7579 Prev_Vis : Entity_Id := Empty;
7580 -- Predecessor of E in Homonym chain
7582 procedure Check_For_Primitive_Subprogram
7583 (Is_Primitive : out Boolean;
7584 Is_Overriding : Boolean := False);
7585 -- If the subprogram being analyzed is a primitive operation of the type
7586 -- of a formal or result, set the Has_Primitive_Operations flag on the
7587 -- type, and set Is_Primitive to True (otherwise set to False). Set the
7588 -- corresponding flag on the entity itself for later use.
7590 procedure Check_Synchronized_Overriding
7591 (Def_Id : Entity_Id;
7592 Overridden_Subp : out Entity_Id);
7593 -- First determine if Def_Id is an entry or a subprogram either defined
7594 -- in the scope of a task or protected type, or is a primitive of such
7595 -- a type. Check whether Def_Id overrides a subprogram of an interface
7596 -- implemented by the synchronized type, return the overridden entity
7599 function Is_Private_Declaration (E : Entity_Id) return Boolean;
7600 -- Check that E is declared in the private part of the current package,
7601 -- or in the package body, where it may hide a previous declaration.
7602 -- We can't use In_Private_Part by itself because this flag is also
7603 -- set when freezing entities, so we must examine the place of the
7604 -- declaration in the tree, and recognize wrapper packages as well.
7606 function Is_Overriding_Alias
7608 New_E : Entity_Id) return Boolean;
7609 -- Check whether new subprogram and old subprogram are both inherited
7610 -- from subprograms that have distinct dispatch table entries. This can
7611 -- occur with derivations from instances with accidental homonyms.
7612 -- The function is conservative given that the converse is only true
7613 -- within instances that contain accidental overloadings.
7615 ------------------------------------
7616 -- Check_For_Primitive_Subprogram --
7617 ------------------------------------
7619 procedure Check_For_Primitive_Subprogram
7620 (Is_Primitive : out Boolean;
7621 Is_Overriding : Boolean := False)
7627 function Visible_Part_Type (T : Entity_Id) return Boolean;
7628 -- Returns true if T is declared in the visible part of the current
7629 -- package scope; otherwise returns false. Assumes that T is declared
7632 procedure Check_Private_Overriding (T : Entity_Id);
7633 -- Checks that if a primitive abstract subprogram of a visible
7634 -- abstract type is declared in a private part, then it must override
7635 -- an abstract subprogram declared in the visible part. Also checks
7636 -- that if a primitive function with a controlling result is declared
7637 -- in a private part, then it must override a function declared in
7638 -- the visible part.
7640 ------------------------------
7641 -- Check_Private_Overriding --
7642 ------------------------------
7644 procedure Check_Private_Overriding (T : Entity_Id) is
7646 if Is_Package_Or_Generic_Package (Current_Scope)
7647 and then In_Private_Part (Current_Scope)
7648 and then Visible_Part_Type (T)
7649 and then not In_Instance
7651 if Is_Abstract_Type (T)
7652 and then Is_Abstract_Subprogram (S)
7653 and then (not Is_Overriding
7654 or else not Is_Abstract_Subprogram (E))
7657 ("abstract subprograms must be visible "
7658 & "(RM 3.9.3(10))!", S);
7660 elsif Ekind (S) = E_Function
7661 and then not Is_Overriding
7663 if Is_Tagged_Type (T)
7664 and then T = Base_Type (Etype (S))
7667 ("private function with tagged result must"
7668 & " override visible-part function", S);
7670 ("\move subprogram to the visible part"
7671 & " (RM 3.9.3(10))", S);
7673 -- AI05-0073: extend this test to the case of a function
7674 -- with a controlling access result.
7676 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
7677 and then Is_Tagged_Type (Designated_Type (Etype (S)))
7679 not Is_Class_Wide_Type (Designated_Type (Etype (S)))
7680 and then Ada_Version >= Ada_2012
7683 ("private function with controlling access result "
7684 & "must override visible-part function", S);
7686 ("\move subprogram to the visible part"
7687 & " (RM 3.9.3(10))", S);
7691 end Check_Private_Overriding;
7693 -----------------------
7694 -- Visible_Part_Type --
7695 -----------------------
7697 function Visible_Part_Type (T : Entity_Id) return Boolean is
7698 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
7702 -- If the entity is a private type, then it must be declared in a
7705 if Ekind (T) in Private_Kind then
7709 -- Otherwise, we traverse the visible part looking for its
7710 -- corresponding declaration. We cannot use the declaration
7711 -- node directly because in the private part the entity of a
7712 -- private type is the one in the full view, which does not
7713 -- indicate that it is the completion of something visible.
7715 N := First (Visible_Declarations (Specification (P)));
7716 while Present (N) loop
7717 if Nkind (N) = N_Full_Type_Declaration
7718 and then Present (Defining_Identifier (N))
7719 and then T = Defining_Identifier (N)
7723 elsif Nkind_In (N, N_Private_Type_Declaration,
7724 N_Private_Extension_Declaration)
7725 and then Present (Defining_Identifier (N))
7726 and then T = Full_View (Defining_Identifier (N))
7735 end Visible_Part_Type;
7737 -- Start of processing for Check_For_Primitive_Subprogram
7740 Is_Primitive := False;
7742 if not Comes_From_Source (S) then
7745 -- If subprogram is at library level, it is not primitive operation
7747 elsif Current_Scope = Standard_Standard then
7750 elsif (Is_Package_Or_Generic_Package (Current_Scope)
7751 and then not In_Package_Body (Current_Scope))
7752 or else Is_Overriding
7754 -- For function, check return type
7756 if Ekind (S) = E_Function then
7757 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
7758 F_Typ := Designated_Type (Etype (S));
7763 B_Typ := Base_Type (F_Typ);
7765 if Scope (B_Typ) = Current_Scope
7766 and then not Is_Class_Wide_Type (B_Typ)
7767 and then not Is_Generic_Type (B_Typ)
7769 Is_Primitive := True;
7770 Set_Has_Primitive_Operations (B_Typ);
7771 Set_Is_Primitive (S);
7772 Check_Private_Overriding (B_Typ);
7776 -- For all subprograms, check formals
7778 Formal := First_Formal (S);
7779 while Present (Formal) loop
7780 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
7781 F_Typ := Designated_Type (Etype (Formal));
7783 F_Typ := Etype (Formal);
7786 B_Typ := Base_Type (F_Typ);
7788 if Ekind (B_Typ) = E_Access_Subtype then
7789 B_Typ := Base_Type (B_Typ);
7792 if Scope (B_Typ) = Current_Scope
7793 and then not Is_Class_Wide_Type (B_Typ)
7794 and then not Is_Generic_Type (B_Typ)
7796 Is_Primitive := True;
7797 Set_Is_Primitive (S);
7798 Set_Has_Primitive_Operations (B_Typ);
7799 Check_Private_Overriding (B_Typ);
7802 Next_Formal (Formal);
7805 end Check_For_Primitive_Subprogram;
7807 -----------------------------------
7808 -- Check_Synchronized_Overriding --
7809 -----------------------------------
7811 procedure Check_Synchronized_Overriding
7812 (Def_Id : Entity_Id;
7813 Overridden_Subp : out Entity_Id)
7815 Ifaces_List : Elist_Id;
7819 function Matches_Prefixed_View_Profile
7820 (Prim_Params : List_Id;
7821 Iface_Params : List_Id) return Boolean;
7822 -- Determine whether a subprogram's parameter profile Prim_Params
7823 -- matches that of a potentially overridden interface subprogram
7824 -- Iface_Params. Also determine if the type of first parameter of
7825 -- Iface_Params is an implemented interface.
7827 -----------------------------------
7828 -- Matches_Prefixed_View_Profile --
7829 -----------------------------------
7831 function Matches_Prefixed_View_Profile
7832 (Prim_Params : List_Id;
7833 Iface_Params : List_Id) return Boolean
7835 Iface_Id : Entity_Id;
7836 Iface_Param : Node_Id;
7837 Iface_Typ : Entity_Id;
7838 Prim_Id : Entity_Id;
7839 Prim_Param : Node_Id;
7840 Prim_Typ : Entity_Id;
7842 function Is_Implemented
7843 (Ifaces_List : Elist_Id;
7844 Iface : Entity_Id) return Boolean;
7845 -- Determine if Iface is implemented by the current task or
7848 --------------------
7849 -- Is_Implemented --
7850 --------------------
7852 function Is_Implemented
7853 (Ifaces_List : Elist_Id;
7854 Iface : Entity_Id) return Boolean
7856 Iface_Elmt : Elmt_Id;
7859 Iface_Elmt := First_Elmt (Ifaces_List);
7860 while Present (Iface_Elmt) loop
7861 if Node (Iface_Elmt) = Iface then
7865 Next_Elmt (Iface_Elmt);
7871 -- Start of processing for Matches_Prefixed_View_Profile
7874 Iface_Param := First (Iface_Params);
7875 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
7877 if Is_Access_Type (Iface_Typ) then
7878 Iface_Typ := Designated_Type (Iface_Typ);
7881 Prim_Param := First (Prim_Params);
7883 -- The first parameter of the potentially overridden subprogram
7884 -- must be an interface implemented by Prim.
7886 if not Is_Interface (Iface_Typ)
7887 or else not Is_Implemented (Ifaces_List, Iface_Typ)
7892 -- The checks on the object parameters are done, move onto the
7893 -- rest of the parameters.
7895 if not In_Scope then
7896 Prim_Param := Next (Prim_Param);
7899 Iface_Param := Next (Iface_Param);
7900 while Present (Iface_Param) and then Present (Prim_Param) loop
7901 Iface_Id := Defining_Identifier (Iface_Param);
7902 Iface_Typ := Find_Parameter_Type (Iface_Param);
7904 Prim_Id := Defining_Identifier (Prim_Param);
7905 Prim_Typ := Find_Parameter_Type (Prim_Param);
7907 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
7908 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
7909 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
7911 Iface_Typ := Designated_Type (Iface_Typ);
7912 Prim_Typ := Designated_Type (Prim_Typ);
7915 -- Case of multiple interface types inside a parameter profile
7917 -- (Obj_Param : in out Iface; ...; Param : Iface)
7919 -- If the interface type is implemented, then the matching type
7920 -- in the primitive should be the implementing record type.
7922 if Ekind (Iface_Typ) = E_Record_Type
7923 and then Is_Interface (Iface_Typ)
7924 and then Is_Implemented (Ifaces_List, Iface_Typ)
7926 if Prim_Typ /= Typ then
7930 -- The two parameters must be both mode and subtype conformant
7932 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
7934 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
7943 -- One of the two lists contains more parameters than the other
7945 if Present (Iface_Param) or else Present (Prim_Param) then
7950 end Matches_Prefixed_View_Profile;
7952 -- Start of processing for Check_Synchronized_Overriding
7955 Overridden_Subp := Empty;
7957 -- Def_Id must be an entry or a subprogram. We should skip predefined
7958 -- primitives internally generated by the frontend; however at this
7959 -- stage predefined primitives are still not fully decorated. As a
7960 -- minor optimization we skip here internally generated subprograms.
7962 if (Ekind (Def_Id) /= E_Entry
7963 and then Ekind (Def_Id) /= E_Function
7964 and then Ekind (Def_Id) /= E_Procedure)
7965 or else not Comes_From_Source (Def_Id)
7970 -- Search for the concurrent declaration since it contains the list
7971 -- of all implemented interfaces. In this case, the subprogram is
7972 -- declared within the scope of a protected or a task type.
7974 if Present (Scope (Def_Id))
7975 and then Is_Concurrent_Type (Scope (Def_Id))
7976 and then not Is_Generic_Actual_Type (Scope (Def_Id))
7978 Typ := Scope (Def_Id);
7981 -- The enclosing scope is not a synchronized type and the subprogram
7984 elsif No (First_Formal (Def_Id)) then
7987 -- The subprogram has formals and hence it may be a primitive of a
7991 Typ := Etype (First_Formal (Def_Id));
7993 if Is_Access_Type (Typ) then
7994 Typ := Directly_Designated_Type (Typ);
7997 if Is_Concurrent_Type (Typ)
7998 and then not Is_Generic_Actual_Type (Typ)
8002 -- This case occurs when the concurrent type is declared within
8003 -- a generic unit. As a result the corresponding record has been
8004 -- built and used as the type of the first formal, we just have
8005 -- to retrieve the corresponding concurrent type.
8007 elsif Is_Concurrent_Record_Type (Typ)
8008 and then not Is_Class_Wide_Type (Typ)
8009 and then Present (Corresponding_Concurrent_Type (Typ))
8011 Typ := Corresponding_Concurrent_Type (Typ);
8019 -- There is no overriding to check if is an inherited operation in a
8020 -- type derivation on for a generic actual.
8022 Collect_Interfaces (Typ, Ifaces_List);
8024 if Is_Empty_Elmt_List (Ifaces_List) then
8028 -- Determine whether entry or subprogram Def_Id overrides a primitive
8029 -- operation that belongs to one of the interfaces in Ifaces_List.
8032 Candidate : Entity_Id := Empty;
8033 Hom : Entity_Id := Empty;
8034 Iface_Typ : Entity_Id;
8035 Subp : Entity_Id := Empty;
8038 -- Traverse the homonym chain, looking for a potentially
8039 -- overridden subprogram that belongs to an implemented
8042 Hom := Current_Entity_In_Scope (Def_Id);
8043 while Present (Hom) loop
8047 or else not Is_Overloadable (Subp)
8048 or else not Is_Primitive (Subp)
8049 or else not Is_Dispatching_Operation (Subp)
8050 or else not Present (Find_Dispatching_Type (Subp))
8051 or else not Is_Interface (Find_Dispatching_Type (Subp))
8055 -- Entries and procedures can override abstract or null
8056 -- interface procedures.
8058 elsif (Ekind (Def_Id) = E_Procedure
8059 or else Ekind (Def_Id) = E_Entry)
8060 and then Ekind (Subp) = E_Procedure
8061 and then Matches_Prefixed_View_Profile
8062 (Parameter_Specifications (Parent (Def_Id)),
8063 Parameter_Specifications (Parent (Subp)))
8067 -- For an overridden subprogram Subp, check whether the mode
8068 -- of its first parameter is correct depending on the kind
8069 -- of synchronized type.
8072 Formal : constant Node_Id := First_Formal (Candidate);
8075 -- In order for an entry or a protected procedure to
8076 -- override, the first parameter of the overridden
8077 -- routine must be of mode "out", "in out" or
8078 -- access-to-variable.
8080 if (Ekind (Candidate) = E_Entry
8081 or else Ekind (Candidate) = E_Procedure)
8082 and then Is_Protected_Type (Typ)
8083 and then Ekind (Formal) /= E_In_Out_Parameter
8084 and then Ekind (Formal) /= E_Out_Parameter
8085 and then Nkind (Parameter_Type (Parent (Formal)))
8086 /= N_Access_Definition
8090 -- All other cases are OK since a task entry or routine
8091 -- does not have a restriction on the mode of the first
8092 -- parameter of the overridden interface routine.
8095 Overridden_Subp := Candidate;
8100 -- Functions can override abstract interface functions
8102 elsif Ekind (Def_Id) = E_Function
8103 and then Ekind (Subp) = E_Function
8104 and then Matches_Prefixed_View_Profile
8105 (Parameter_Specifications (Parent (Def_Id)),
8106 Parameter_Specifications (Parent (Subp)))
8107 and then Etype (Result_Definition (Parent (Def_Id))) =
8108 Etype (Result_Definition (Parent (Subp)))
8110 Overridden_Subp := Subp;
8114 Hom := Homonym (Hom);
8117 -- After examining all candidates for overriding, we are left with
8118 -- the best match which is a mode incompatible interface routine.
8119 -- Do not emit an error if the Expander is active since this error
8120 -- will be detected later on after all concurrent types are
8121 -- expanded and all wrappers are built. This check is meant for
8122 -- spec-only compilations.
8124 if Present (Candidate) and then not Expander_Active then
8126 Find_Parameter_Type (Parent (First_Formal (Candidate)));
8128 -- Def_Id is primitive of a protected type, declared inside the
8129 -- type, and the candidate is primitive of a limited or
8130 -- synchronized interface.
8133 and then Is_Protected_Type (Typ)
8135 (Is_Limited_Interface (Iface_Typ)
8136 or else Is_Protected_Interface (Iface_Typ)
8137 or else Is_Synchronized_Interface (Iface_Typ)
8138 or else Is_Task_Interface (Iface_Typ))
8140 Error_Msg_PT (Parent (Typ), Candidate);
8144 Overridden_Subp := Candidate;
8147 end Check_Synchronized_Overriding;
8149 ----------------------------
8150 -- Is_Private_Declaration --
8151 ----------------------------
8153 function Is_Private_Declaration (E : Entity_Id) return Boolean is
8154 Priv_Decls : List_Id;
8155 Decl : constant Node_Id := Unit_Declaration_Node (E);
8158 if Is_Package_Or_Generic_Package (Current_Scope)
8159 and then In_Private_Part (Current_Scope)
8162 Private_Declarations (
8163 Specification (Unit_Declaration_Node (Current_Scope)));
8165 return In_Package_Body (Current_Scope)
8167 (Is_List_Member (Decl)
8168 and then List_Containing (Decl) = Priv_Decls)
8169 or else (Nkind (Parent (Decl)) = N_Package_Specification
8172 (Defining_Entity (Parent (Decl)))
8173 and then List_Containing (Parent (Parent (Decl)))
8178 end Is_Private_Declaration;
8180 --------------------------
8181 -- Is_Overriding_Alias --
8182 --------------------------
8184 function Is_Overriding_Alias
8186 New_E : Entity_Id) return Boolean
8188 AO : constant Entity_Id := Alias (Old_E);
8189 AN : constant Entity_Id := Alias (New_E);
8192 return Scope (AO) /= Scope (AN)
8193 or else No (DTC_Entity (AO))
8194 or else No (DTC_Entity (AN))
8195 or else DT_Position (AO) = DT_Position (AN);
8196 end Is_Overriding_Alias;
8198 -- Start of processing for New_Overloaded_Entity
8201 -- We need to look for an entity that S may override. This must be a
8202 -- homonym in the current scope, so we look for the first homonym of
8203 -- S in the current scope as the starting point for the search.
8205 E := Current_Entity_In_Scope (S);
8207 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
8208 -- They are directly added to the list of primitive operations of
8209 -- Derived_Type, unless this is a rederivation in the private part
8210 -- of an operation that was already derived in the visible part of
8211 -- the current package.
8213 if Ada_Version >= Ada_2005
8214 and then Present (Derived_Type)
8215 and then Present (Alias (S))
8216 and then Is_Dispatching_Operation (Alias (S))
8217 and then Present (Find_Dispatching_Type (Alias (S)))
8218 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
8220 -- For private types, when the full-view is processed we propagate to
8221 -- the full view the non-overridden entities whose attribute "alias"
8222 -- references an interface primitive. These entities were added by
8223 -- Derive_Subprograms to ensure that interface primitives are
8226 -- Inside_Freeze_Actions is non zero when S corresponds with an
8227 -- internal entity that links an interface primitive with its
8228 -- covering primitive through attribute Interface_Alias (see
8229 -- Add_Internal_Interface_Entities).
8231 if Inside_Freezing_Actions = 0
8232 and then Is_Package_Or_Generic_Package (Current_Scope)
8233 and then In_Private_Part (Current_Scope)
8234 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
8235 and then Nkind (Parent (S)) = N_Full_Type_Declaration
8236 and then Full_View (Defining_Identifier (Parent (E)))
8237 = Defining_Identifier (Parent (S))
8238 and then Alias (E) = Alias (S)
8240 Check_Operation_From_Private_View (S, E);
8241 Set_Is_Dispatching_Operation (S);
8246 Enter_Overloaded_Entity (S);
8247 Check_Dispatching_Operation (S, Empty);
8248 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
8254 -- If there is no homonym then this is definitely not overriding
8257 Enter_Overloaded_Entity (S);
8258 Check_Dispatching_Operation (S, Empty);
8259 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
8261 -- If subprogram has an explicit declaration, check whether it
8262 -- has an overriding indicator.
8264 if Comes_From_Source (S) then
8265 Check_Synchronized_Overriding (S, Overridden_Subp);
8267 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
8268 -- it may have overridden some hidden inherited primitive. Update
8269 -- Overridden_Subp to avoid spurious errors when checking the
8270 -- overriding indicator.
8272 if Ada_Version >= Ada_2012
8273 and then No (Overridden_Subp)
8274 and then Is_Dispatching_Operation (S)
8275 and then Present (Overridden_Operation (S))
8277 Overridden_Subp := Overridden_Operation (S);
8280 Check_Overriding_Indicator
8281 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
8284 -- If there is a homonym that is not overloadable, then we have an
8285 -- error, except for the special cases checked explicitly below.
8287 elsif not Is_Overloadable (E) then
8289 -- Check for spurious conflict produced by a subprogram that has the
8290 -- same name as that of the enclosing generic package. The conflict
8291 -- occurs within an instance, between the subprogram and the renaming
8292 -- declaration for the package. After the subprogram, the package
8293 -- renaming declaration becomes hidden.
8295 if Ekind (E) = E_Package
8296 and then Present (Renamed_Object (E))
8297 and then Renamed_Object (E) = Current_Scope
8298 and then Nkind (Parent (Renamed_Object (E))) =
8299 N_Package_Specification
8300 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
8303 Set_Is_Immediately_Visible (E, False);
8304 Enter_Overloaded_Entity (S);
8305 Set_Homonym (S, Homonym (E));
8306 Check_Dispatching_Operation (S, Empty);
8307 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
8309 -- If the subprogram is implicit it is hidden by the previous
8310 -- declaration. However if it is dispatching, it must appear in the
8311 -- dispatch table anyway, because it can be dispatched to even if it
8312 -- cannot be called directly.
8314 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
8315 Set_Scope (S, Current_Scope);
8317 if Is_Dispatching_Operation (Alias (S)) then
8318 Check_Dispatching_Operation (S, Empty);
8324 Error_Msg_Sloc := Sloc (E);
8326 -- Generate message, with useful additional warning if in generic
8328 if Is_Generic_Unit (E) then
8329 Error_Msg_N ("previous generic unit cannot be overloaded", S);
8330 Error_Msg_N ("\& conflicts with declaration#", S);
8332 Error_Msg_N ("& conflicts with declaration#", S);
8338 -- E exists and is overloadable
8341 Check_Synchronized_Overriding (S, Overridden_Subp);
8343 -- Loop through E and its homonyms to determine if any of them is
8344 -- the candidate for overriding by S.
8346 while Present (E) loop
8348 -- Definitely not interesting if not in the current scope
8350 if Scope (E) /= Current_Scope then
8353 -- Ada 2012 (AI05-0165): For internally generated bodies of
8354 -- null procedures locate the internally generated spec. We
8355 -- enforce mode conformance since a tagged type may inherit
8356 -- from interfaces several null primitives which differ only
8357 -- in the mode of the formals.
8359 elsif not Comes_From_Source (S)
8360 and then Is_Null_Procedure (S)
8361 and then not Mode_Conformant (E, S)
8365 -- Check if we have type conformance
8367 elsif Type_Conformant (E, S) then
8369 -- If the old and new entities have the same profile and one
8370 -- is not the body of the other, then this is an error, unless
8371 -- one of them is implicitly declared.
8373 -- There are some cases when both can be implicit, for example
8374 -- when both a literal and a function that overrides it are
8375 -- inherited in a derivation, or when an inherited operation
8376 -- of a tagged full type overrides the inherited operation of
8377 -- a private extension. Ada 83 had a special rule for the
8378 -- literal case. In Ada95, the later implicit operation hides
8379 -- the former, and the literal is always the former. In the
8380 -- odd case where both are derived operations declared at the
8381 -- same point, both operations should be declared, and in that
8382 -- case we bypass the following test and proceed to the next
8383 -- part. This can only occur for certain obscure cases in
8384 -- instances, when an operation on a type derived from a formal
8385 -- private type does not override a homograph inherited from
8386 -- the actual. In subsequent derivations of such a type, the
8387 -- DT positions of these operations remain distinct, if they
8390 if Present (Alias (S))
8391 and then (No (Alias (E))
8392 or else Comes_From_Source (E)
8393 or else Is_Abstract_Subprogram (S)
8395 (Is_Dispatching_Operation (E)
8396 and then Is_Overriding_Alias (E, S)))
8397 and then Ekind (E) /= E_Enumeration_Literal
8399 -- When an derived operation is overloaded it may be due to
8400 -- the fact that the full view of a private extension
8401 -- re-inherits. It has to be dealt with.
8403 if Is_Package_Or_Generic_Package (Current_Scope)
8404 and then In_Private_Part (Current_Scope)
8406 Check_Operation_From_Private_View (S, E);
8409 -- In any case the implicit operation remains hidden by the
8410 -- existing declaration, which is overriding. Indicate that
8411 -- E overrides the operation from which S is inherited.
8413 if Present (Alias (S)) then
8414 Set_Overridden_Operation (E, Alias (S));
8416 Set_Overridden_Operation (E, S);
8419 if Comes_From_Source (E) then
8420 Check_Overriding_Indicator (E, S, Is_Primitive => False);
8425 -- Within an instance, the renaming declarations for actual
8426 -- subprograms may become ambiguous, but they do not hide each
8429 elsif Ekind (E) /= E_Entry
8430 and then not Comes_From_Source (E)
8431 and then not Is_Generic_Instance (E)
8432 and then (Present (Alias (E))
8433 or else Is_Intrinsic_Subprogram (E))
8434 and then (not In_Instance
8435 or else No (Parent (E))
8436 or else Nkind (Unit_Declaration_Node (E)) /=
8437 N_Subprogram_Renaming_Declaration)
8439 -- A subprogram child unit is not allowed to override an
8440 -- inherited subprogram (10.1.1(20)).
8442 if Is_Child_Unit (S) then
8444 ("child unit overrides inherited subprogram in parent",
8449 if Is_Non_Overriding_Operation (E, S) then
8450 Enter_Overloaded_Entity (S);
8452 if No (Derived_Type)
8453 or else Is_Tagged_Type (Derived_Type)
8455 Check_Dispatching_Operation (S, Empty);
8461 -- E is a derived operation or an internal operator which
8462 -- is being overridden. Remove E from further visibility.
8463 -- Furthermore, if E is a dispatching operation, it must be
8464 -- replaced in the list of primitive operations of its type
8465 -- (see Override_Dispatching_Operation).
8467 Overridden_Subp := E;
8473 Prev := First_Entity (Current_Scope);
8474 while Present (Prev)
8475 and then Next_Entity (Prev) /= E
8480 -- It is possible for E to be in the current scope and
8481 -- yet not in the entity chain. This can only occur in a
8482 -- generic context where E is an implicit concatenation
8483 -- in the formal part, because in a generic body the
8484 -- entity chain starts with the formals.
8487 (Present (Prev) or else Chars (E) = Name_Op_Concat);
8489 -- E must be removed both from the entity_list of the
8490 -- current scope, and from the visibility chain
8492 if Debug_Flag_E then
8493 Write_Str ("Override implicit operation ");
8494 Write_Int (Int (E));
8498 -- If E is a predefined concatenation, it stands for four
8499 -- different operations. As a result, a single explicit
8500 -- declaration does not hide it. In a possible ambiguous
8501 -- situation, Disambiguate chooses the user-defined op,
8502 -- so it is correct to retain the previous internal one.
8504 if Chars (E) /= Name_Op_Concat
8505 or else Ekind (E) /= E_Operator
8507 -- For nondispatching derived operations that are
8508 -- overridden by a subprogram declared in the private
8509 -- part of a package, we retain the derived subprogram
8510 -- but mark it as not immediately visible. If the
8511 -- derived operation was declared in the visible part
8512 -- then this ensures that it will still be visible
8513 -- outside the package with the proper signature
8514 -- (calls from outside must also be directed to this
8515 -- version rather than the overriding one, unlike the
8516 -- dispatching case). Calls from inside the package
8517 -- will still resolve to the overriding subprogram
8518 -- since the derived one is marked as not visible
8519 -- within the package.
8521 -- If the private operation is dispatching, we achieve
8522 -- the overriding by keeping the implicit operation
8523 -- but setting its alias to be the overriding one. In
8524 -- this fashion the proper body is executed in all
8525 -- cases, but the original signature is used outside
8528 -- If the overriding is not in the private part, we
8529 -- remove the implicit operation altogether.
8531 if Is_Private_Declaration (S) then
8532 if not Is_Dispatching_Operation (E) then
8533 Set_Is_Immediately_Visible (E, False);
8535 -- Work done in Override_Dispatching_Operation,
8536 -- so nothing else need to be done here.
8542 -- Find predecessor of E in Homonym chain
8544 if E = Current_Entity (E) then
8547 Prev_Vis := Current_Entity (E);
8548 while Homonym (Prev_Vis) /= E loop
8549 Prev_Vis := Homonym (Prev_Vis);
8553 if Prev_Vis /= Empty then
8555 -- Skip E in the visibility chain
8557 Set_Homonym (Prev_Vis, Homonym (E));
8560 Set_Name_Entity_Id (Chars (E), Homonym (E));
8563 Set_Next_Entity (Prev, Next_Entity (E));
8565 if No (Next_Entity (Prev)) then
8566 Set_Last_Entity (Current_Scope, Prev);
8571 Enter_Overloaded_Entity (S);
8573 -- For entities generated by Derive_Subprograms the
8574 -- overridden operation is the inherited primitive
8575 -- (which is available through the attribute alias).
8577 if not (Comes_From_Source (E))
8578 and then Is_Dispatching_Operation (E)
8579 and then Find_Dispatching_Type (E) =
8580 Find_Dispatching_Type (S)
8581 and then Present (Alias (E))
8582 and then Comes_From_Source (Alias (E))
8584 Set_Overridden_Operation (S, Alias (E));
8586 -- Normal case of setting entity as overridden
8588 -- Note: Static_Initialization and Overridden_Operation
8589 -- attributes use the same field in subprogram entities.
8590 -- Static_Initialization is only defined for internal
8591 -- initialization procedures, where Overridden_Operation
8592 -- is irrelevant. Therefore the setting of this attribute
8593 -- must check whether the target is an init_proc.
8595 elsif not Is_Init_Proc (S) then
8596 Set_Overridden_Operation (S, E);
8599 Check_Overriding_Indicator (S, E, Is_Primitive => True);
8601 -- If S is a user-defined subprogram or a null procedure
8602 -- expanded to override an inherited null procedure, or a
8603 -- predefined dispatching primitive then indicate that E
8604 -- overrides the operation from which S is inherited.
8606 if Comes_From_Source (S)
8608 (Present (Parent (S))
8610 Nkind (Parent (S)) = N_Procedure_Specification
8612 Null_Present (Parent (S)))
8614 (Present (Alias (E))
8616 Is_Predefined_Dispatching_Operation (Alias (E)))
8618 if Present (Alias (E)) then
8619 Set_Overridden_Operation (S, Alias (E));
8623 if Is_Dispatching_Operation (E) then
8625 -- An overriding dispatching subprogram inherits the
8626 -- convention of the overridden subprogram (AI-117).
8628 Set_Convention (S, Convention (E));
8629 Check_Dispatching_Operation (S, E);
8632 Check_Dispatching_Operation (S, Empty);
8635 Check_For_Primitive_Subprogram
8636 (Is_Primitive_Subp, Is_Overriding => True);
8637 goto Check_Inequality;
8640 -- Apparent redeclarations in instances can occur when two
8641 -- formal types get the same actual type. The subprograms in
8642 -- in the instance are legal, even if not callable from the
8643 -- outside. Calls from within are disambiguated elsewhere.
8644 -- For dispatching operations in the visible part, the usual
8645 -- rules apply, and operations with the same profile are not
8648 elsif (In_Instance_Visible_Part
8649 and then not Is_Dispatching_Operation (E))
8650 or else In_Instance_Not_Visible
8654 -- Here we have a real error (identical profile)
8657 Error_Msg_Sloc := Sloc (E);
8659 -- Avoid cascaded errors if the entity appears in
8660 -- subsequent calls.
8662 Set_Scope (S, Current_Scope);
8664 -- Generate error, with extra useful warning for the case
8665 -- of a generic instance with no completion.
8667 if Is_Generic_Instance (S)
8668 and then not Has_Completion (E)
8671 ("instantiation cannot provide body for&", S);
8672 Error_Msg_N ("\& conflicts with declaration#", S);
8674 Error_Msg_N ("& conflicts with declaration#", S);
8681 -- If one subprogram has an access parameter and the other
8682 -- a parameter of an access type, calls to either might be
8683 -- ambiguous. Verify that parameters match except for the
8684 -- access parameter.
8686 if May_Hide_Profile then
8692 F1 := First_Formal (S);
8693 F2 := First_Formal (E);
8694 while Present (F1) and then Present (F2) loop
8695 if Is_Access_Type (Etype (F1)) then
8696 if not Is_Access_Type (Etype (F2))
8697 or else not Conforming_Types
8698 (Designated_Type (Etype (F1)),
8699 Designated_Type (Etype (F2)),
8702 May_Hide_Profile := False;
8706 not Conforming_Types
8707 (Etype (F1), Etype (F2), Type_Conformant)
8709 May_Hide_Profile := False;
8720 Error_Msg_NE ("calls to& may be ambiguous?", S, S);
8729 -- On exit, we know that S is a new entity
8731 Enter_Overloaded_Entity (S);
8732 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
8733 Check_Overriding_Indicator
8734 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
8736 -- Overloading is not allowed in SPARK, except for operators
8738 if Nkind (S) /= N_Defining_Operator_Symbol then
8739 Error_Msg_Sloc := Sloc (Homonym (S));
8740 Check_SPARK_Restriction
8741 ("overloading not allowed with entity#", S);
8744 -- If S is a derived operation for an untagged type then by
8745 -- definition it's not a dispatching operation (even if the parent
8746 -- operation was dispatching), so Check_Dispatching_Operation is not
8747 -- called in that case.
8749 if No (Derived_Type)
8750 or else Is_Tagged_Type (Derived_Type)
8752 Check_Dispatching_Operation (S, Empty);
8756 -- If this is a user-defined equality operator that is not a derived
8757 -- subprogram, create the corresponding inequality. If the operation is
8758 -- dispatching, the expansion is done elsewhere, and we do not create
8759 -- an explicit inequality operation.
8761 <<Check_Inequality>>
8762 if Chars (S) = Name_Op_Eq
8763 and then Etype (S) = Standard_Boolean
8764 and then Present (Parent (S))
8765 and then not Is_Dispatching_Operation (S)
8767 Make_Inequality_Operator (S);
8769 if Ada_Version >= Ada_2012 then
8770 Check_Untagged_Equality (S);
8773 end New_Overloaded_Entity;
8775 ---------------------
8776 -- Process_Formals --
8777 ---------------------
8779 procedure Process_Formals
8781 Related_Nod : Node_Id)
8783 Param_Spec : Node_Id;
8785 Formal_Type : Entity_Id;
8789 Num_Out_Params : Nat := 0;
8790 First_Out_Param : Entity_Id := Empty;
8791 -- Used for setting Is_Only_Out_Parameter
8793 function Designates_From_With_Type (Typ : Entity_Id) return Boolean;
8794 -- Determine whether an access type designates a type coming from a
8797 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
8798 -- Check whether the default has a class-wide type. After analysis the
8799 -- default has the type of the formal, so we must also check explicitly
8800 -- for an access attribute.
8802 -------------------------------
8803 -- Designates_From_With_Type --
8804 -------------------------------
8806 function Designates_From_With_Type (Typ : Entity_Id) return Boolean is
8807 Desig : Entity_Id := Typ;
8810 if Is_Access_Type (Desig) then
8811 Desig := Directly_Designated_Type (Desig);
8814 if Is_Class_Wide_Type (Desig) then
8815 Desig := Root_Type (Desig);
8819 Ekind (Desig) = E_Incomplete_Type
8820 and then From_With_Type (Desig);
8821 end Designates_From_With_Type;
8823 ---------------------------
8824 -- Is_Class_Wide_Default --
8825 ---------------------------
8827 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
8829 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
8830 or else (Nkind (D) = N_Attribute_Reference
8831 and then Attribute_Name (D) = Name_Access
8832 and then Is_Class_Wide_Type (Etype (Prefix (D))));
8833 end Is_Class_Wide_Default;
8835 -- Start of processing for Process_Formals
8838 -- In order to prevent premature use of the formals in the same formal
8839 -- part, the Ekind is left undefined until all default expressions are
8840 -- analyzed. The Ekind is established in a separate loop at the end.
8842 Param_Spec := First (T);
8843 while Present (Param_Spec) loop
8844 Formal := Defining_Identifier (Param_Spec);
8845 Set_Never_Set_In_Source (Formal, True);
8846 Enter_Name (Formal);
8848 -- Case of ordinary parameters
8850 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
8851 Find_Type (Parameter_Type (Param_Spec));
8852 Ptype := Parameter_Type (Param_Spec);
8854 if Ptype = Error then
8858 Formal_Type := Entity (Ptype);
8860 if Is_Incomplete_Type (Formal_Type)
8862 (Is_Class_Wide_Type (Formal_Type)
8863 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
8865 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
8866 -- primitive operations, as long as their completion is
8867 -- in the same declarative part. If in the private part
8868 -- this means that the type cannot be a Taft-amendment type.
8869 -- Check is done on package exit. For access to subprograms,
8870 -- the use is legal for Taft-amendment types.
8872 if Is_Tagged_Type (Formal_Type) then
8873 if Ekind (Scope (Current_Scope)) = E_Package
8874 and then not From_With_Type (Formal_Type)
8875 and then not Is_Class_Wide_Type (Formal_Type)
8878 (Parent (T), N_Access_Function_Definition,
8879 N_Access_Procedure_Definition)
8883 Private_Dependents (Base_Type (Formal_Type)));
8885 -- Freezing is delayed to ensure that Register_Prim
8886 -- will get called for this operation, which is needed
8887 -- in cases where static dispatch tables aren't built.
8888 -- (Note that the same is done for controlling access
8889 -- parameter cases in function Access_Definition.)
8891 Set_Has_Delayed_Freeze (Current_Scope);
8895 -- Special handling of Value_Type for CIL case
8897 elsif Is_Value_Type (Formal_Type) then
8900 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
8901 N_Access_Procedure_Definition)
8904 -- AI05-0151: Tagged incomplete types are allowed in all
8905 -- formal parts. Untagged incomplete types are not allowed
8908 if Ada_Version >= Ada_2012 then
8909 if Is_Tagged_Type (Formal_Type) then
8912 elsif Nkind_In (Parent (Parent (T)), N_Accept_Statement,
8917 ("invalid use of untagged incomplete type&",
8918 Ptype, Formal_Type);
8923 ("invalid use of incomplete type&",
8924 Param_Spec, Formal_Type);
8926 -- Further checks on the legality of incomplete types
8927 -- in formal parts are delayed until the freeze point
8928 -- of the enclosing subprogram or access to subprogram.
8932 elsif Ekind (Formal_Type) = E_Void then
8934 ("premature use of&",
8935 Parameter_Type (Param_Spec), Formal_Type);
8938 -- Ada 2005 (AI-231): Create and decorate an internal subtype
8939 -- declaration corresponding to the null-excluding type of the
8940 -- formal in the enclosing scope. Finally, replace the parameter
8941 -- type of the formal with the internal subtype.
8943 if Ada_Version >= Ada_2005
8944 and then Null_Exclusion_Present (Param_Spec)
8946 if not Is_Access_Type (Formal_Type) then
8948 ("`NOT NULL` allowed only for an access type", Param_Spec);
8951 if Can_Never_Be_Null (Formal_Type)
8952 and then Comes_From_Source (Related_Nod)
8955 ("`NOT NULL` not allowed (& already excludes null)",
8956 Param_Spec, Formal_Type);
8960 Create_Null_Excluding_Itype
8962 Related_Nod => Related_Nod,
8963 Scope_Id => Scope (Current_Scope));
8965 -- If the designated type of the itype is an itype we
8966 -- decorate it with the Has_Delayed_Freeze attribute to
8967 -- avoid problems with the backend.
8970 -- type T is access procedure;
8971 -- procedure Op (O : not null T);
8973 if Is_Itype (Directly_Designated_Type (Formal_Type)) then
8974 Set_Has_Delayed_Freeze (Formal_Type);
8979 -- An access formal type
8983 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
8985 -- No need to continue if we already notified errors
8987 if not Present (Formal_Type) then
8991 -- Ada 2005 (AI-254)
8994 AD : constant Node_Id :=
8995 Access_To_Subprogram_Definition
8996 (Parameter_Type (Param_Spec));
8998 if Present (AD) and then Protected_Present (AD) then
9000 Replace_Anonymous_Access_To_Protected_Subprogram
9006 Set_Etype (Formal, Formal_Type);
9008 Default := Expression (Param_Spec);
9010 if Present (Default) then
9011 Check_SPARK_Restriction
9012 ("default expression is not allowed", Default);
9014 if Out_Present (Param_Spec) then
9016 ("default initialization only allowed for IN parameters",
9020 -- Do the special preanalysis of the expression (see section on
9021 -- "Handling of Default Expressions" in the spec of package Sem).
9023 Preanalyze_Spec_Expression (Default, Formal_Type);
9025 -- An access to constant cannot be the default for
9026 -- an access parameter that is an access to variable.
9028 if Ekind (Formal_Type) = E_Anonymous_Access_Type
9029 and then not Is_Access_Constant (Formal_Type)
9030 and then Is_Access_Type (Etype (Default))
9031 and then Is_Access_Constant (Etype (Default))
9034 ("formal that is access to variable cannot be initialized " &
9035 "with an access-to-constant expression", Default);
9038 -- Check that the designated type of an access parameter's default
9039 -- is not a class-wide type unless the parameter's designated type
9040 -- is also class-wide.
9042 if Ekind (Formal_Type) = E_Anonymous_Access_Type
9043 and then not Designates_From_With_Type (Formal_Type)
9044 and then Is_Class_Wide_Default (Default)
9045 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
9048 ("access to class-wide expression not allowed here", Default);
9051 -- Check incorrect use of dynamically tagged expressions
9053 if Is_Tagged_Type (Formal_Type) then
9054 Check_Dynamically_Tagged_Expression
9057 Related_Nod => Default);
9061 -- Ada 2005 (AI-231): Static checks
9063 if Ada_Version >= Ada_2005
9064 and then Is_Access_Type (Etype (Formal))
9065 and then Can_Never_Be_Null (Etype (Formal))
9067 Null_Exclusion_Static_Checks (Param_Spec);
9074 -- If this is the formal part of a function specification, analyze the
9075 -- subtype mark in the context where the formals are visible but not
9076 -- yet usable, and may hide outer homographs.
9078 if Nkind (Related_Nod) = N_Function_Specification then
9079 Analyze_Return_Type (Related_Nod);
9082 -- Now set the kind (mode) of each formal
9084 Param_Spec := First (T);
9085 while Present (Param_Spec) loop
9086 Formal := Defining_Identifier (Param_Spec);
9087 Set_Formal_Mode (Formal);
9089 if Ekind (Formal) = E_In_Parameter then
9090 Set_Default_Value (Formal, Expression (Param_Spec));
9092 if Present (Expression (Param_Spec)) then
9093 Default := Expression (Param_Spec);
9095 if Is_Scalar_Type (Etype (Default)) then
9097 (Parameter_Type (Param_Spec)) /= N_Access_Definition
9099 Formal_Type := Entity (Parameter_Type (Param_Spec));
9102 Formal_Type := Access_Definition
9103 (Related_Nod, Parameter_Type (Param_Spec));
9106 Apply_Scalar_Range_Check (Default, Formal_Type);
9110 elsif Ekind (Formal) = E_Out_Parameter then
9111 Num_Out_Params := Num_Out_Params + 1;
9113 if Num_Out_Params = 1 then
9114 First_Out_Param := Formal;
9117 elsif Ekind (Formal) = E_In_Out_Parameter then
9118 Num_Out_Params := Num_Out_Params + 1;
9124 if Present (First_Out_Param) and then Num_Out_Params = 1 then
9125 Set_Is_Only_Out_Parameter (First_Out_Param);
9127 end Process_Formals;
9133 procedure Process_PPCs
9135 Spec_Id : Entity_Id;
9136 Body_Id : Entity_Id)
9138 Loc : constant Source_Ptr := Sloc (N);
9142 Designator : Entity_Id;
9143 -- Subprogram designator, set from Spec_Id if present, else Body_Id
9145 Precond : Node_Id := Empty;
9146 -- Set non-Empty if we prepend precondition to the declarations. This
9147 -- is used to hook up inherited preconditions (adding the condition
9148 -- expression with OR ELSE, and adding the message).
9150 Inherited_Precond : Node_Id;
9151 -- Precondition inherited from parent subprogram
9153 Inherited : constant Subprogram_List :=
9154 Inherited_Subprograms (Spec_Id);
9155 -- List of subprograms inherited by this subprogram
9157 Plist : List_Id := No_List;
9158 -- List of generated postconditions
9160 function Grab_PPC (Pspec : Entity_Id := Empty) return Node_Id;
9161 -- Prag contains an analyzed precondition or postcondition pragma. This
9162 -- function copies the pragma, changes it to the corresponding Check
9163 -- pragma and returns the Check pragma as the result. If Pspec is non-
9164 -- empty, this is the case of inheriting a PPC, where we must change
9165 -- references to parameters of the inherited subprogram to point to the
9166 -- corresponding parameters of the current subprogram.
9168 function Invariants_Or_Predicates_Present return Boolean;
9169 -- Determines if any invariants or predicates are present for any OUT
9170 -- or IN OUT parameters of the subprogram, or (for a function) if the
9171 -- return value has an invariant.
9177 function Grab_PPC (Pspec : Entity_Id := Empty) return Node_Id is
9178 Nam : constant Name_Id := Pragma_Name (Prag);
9183 -- Prepare map if this is the case where we have to map entities of
9184 -- arguments in the overridden subprogram to corresponding entities
9185 -- of the current subprogram.
9196 Map := New_Elmt_List;
9197 PF := First_Formal (Pspec);
9198 CF := First_Formal (Designator);
9199 while Present (PF) loop
9200 Append_Elmt (PF, Map);
9201 Append_Elmt (CF, Map);
9208 -- Now we can copy the tree, doing any required substitutions
9210 CP := New_Copy_Tree (Prag, Map => Map, New_Scope => Current_Scope);
9212 -- Set Analyzed to false, since we want to reanalyze the check
9213 -- procedure. Note that it is only at the outer level that we
9214 -- do this fiddling, for the spec cases, the already preanalyzed
9215 -- parameters are not affected.
9217 Set_Analyzed (CP, False);
9219 -- We also make sure Comes_From_Source is False for the copy
9221 Set_Comes_From_Source (CP, False);
9223 -- For a postcondition pragma within a generic, preserve the pragma
9224 -- for later expansion.
9226 if Nam = Name_Postcondition
9227 and then not Expander_Active
9232 -- Change copy of pragma into corresponding pragma Check
9234 Prepend_To (Pragma_Argument_Associations (CP),
9235 Make_Pragma_Argument_Association (Sloc (Prag),
9236 Expression => Make_Identifier (Loc, Nam)));
9237 Set_Pragma_Identifier (CP, Make_Identifier (Sloc (Prag), Name_Check));
9239 -- If this is inherited case and the current message starts with
9240 -- "failed p", we change it to "failed inherited p...".
9242 if Present (Pspec) then
9244 Msg : constant Node_Id :=
9245 Last (Pragma_Argument_Associations (CP));
9248 if Chars (Msg) = Name_Message then
9249 String_To_Name_Buffer (Strval (Expression (Msg)));
9251 if Name_Buffer (1 .. 8) = "failed p" then
9252 Insert_Str_In_Name_Buffer ("inherited ", 8);
9254 (Expression (Last (Pragma_Argument_Associations (CP))),
9255 String_From_Name_Buffer);
9261 -- Return the check pragma
9266 --------------------------------------
9267 -- Invariants_Or_Predicates_Present --
9268 --------------------------------------
9270 function Invariants_Or_Predicates_Present return Boolean is
9274 -- Check function return result
9276 if Ekind (Designator) /= E_Procedure
9277 and then Has_Invariants (Etype (Designator))
9284 Formal := First_Formal (Designator);
9285 while Present (Formal) loop
9286 if Ekind (Formal) /= E_In_Parameter
9288 (Has_Invariants (Etype (Formal))
9289 or else Present (Predicate_Function (Etype (Formal))))
9294 Next_Formal (Formal);
9298 end Invariants_Or_Predicates_Present;
9300 -- Start of processing for Process_PPCs
9303 -- Capture designator from spec if present, else from body
9305 if Present (Spec_Id) then
9306 Designator := Spec_Id;
9308 Designator := Body_Id;
9311 -- Grab preconditions from spec
9313 if Present (Spec_Id) then
9315 -- Loop through PPC pragmas from spec. Note that preconditions from
9316 -- the body will be analyzed and converted when we scan the body
9317 -- declarations below.
9319 Prag := Spec_PPC_List (Contract (Spec_Id));
9320 while Present (Prag) loop
9321 if Pragma_Name (Prag) = Name_Precondition then
9323 -- For Pre (or Precondition pragma), we simply prepend the
9324 -- pragma to the list of declarations right away so that it
9325 -- will be executed at the start of the procedure. Note that
9326 -- this processing reverses the order of the list, which is
9327 -- what we want since new entries were chained to the head of
9328 -- the list. There can be more than one precondition when we
9329 -- use pragma Precondition.
9331 if not Class_Present (Prag) then
9332 Prepend (Grab_PPC, Declarations (N));
9334 -- For Pre'Class there can only be one pragma, and we save
9335 -- it in Precond for now. We will add inherited Pre'Class
9336 -- stuff before inserting this pragma in the declarations.
9338 Precond := Grab_PPC;
9342 Prag := Next_Pragma (Prag);
9345 -- Now deal with inherited preconditions
9347 for J in Inherited'Range loop
9348 Prag := Spec_PPC_List (Contract (Inherited (J)));
9350 while Present (Prag) loop
9351 if Pragma_Name (Prag) = Name_Precondition
9352 and then Class_Present (Prag)
9354 Inherited_Precond := Grab_PPC (Inherited (J));
9356 -- No precondition so far, so establish this as the first
9358 if No (Precond) then
9359 Precond := Inherited_Precond;
9361 -- Here we already have a precondition, add inherited one
9364 -- Add new precondition to old one using OR ELSE
9367 New_Expr : constant Node_Id :=
9371 (Pragma_Argument_Associations
9372 (Inherited_Precond))));
9373 Old_Expr : constant Node_Id :=
9377 (Pragma_Argument_Associations
9381 if Paren_Count (Old_Expr) = 0 then
9382 Set_Paren_Count (Old_Expr, 1);
9385 if Paren_Count (New_Expr) = 0 then
9386 Set_Paren_Count (New_Expr, 1);
9390 Make_Or_Else (Sloc (Old_Expr),
9391 Left_Opnd => Relocate_Node (Old_Expr),
9392 Right_Opnd => New_Expr));
9395 -- Add new message in the form:
9397 -- failed precondition from bla
9398 -- also failed inherited precondition from bla
9401 -- Skip this if exception locations are suppressed
9403 if not Exception_Locations_Suppressed then
9405 New_Msg : constant Node_Id :=
9408 (Pragma_Argument_Associations
9409 (Inherited_Precond)));
9410 Old_Msg : constant Node_Id :=
9413 (Pragma_Argument_Associations
9416 Start_String (Strval (Old_Msg));
9417 Store_String_Chars (ASCII.LF & " also ");
9418 Store_String_Chars (Strval (New_Msg));
9419 Set_Strval (Old_Msg, End_String);
9425 Prag := Next_Pragma (Prag);
9429 -- If we have built a precondition for Pre'Class (including any
9430 -- Pre'Class aspects inherited from parent subprograms), then we
9431 -- insert this composite precondition at this stage.
9433 if Present (Precond) then
9434 Prepend (Precond, Declarations (N));
9438 -- Build postconditions procedure if needed and prepend the following
9439 -- declaration to the start of the declarations for the subprogram.
9441 -- procedure _postconditions [(_Result : resulttype)] is
9443 -- pragma Check (Postcondition, condition [,message]);
9444 -- pragma Check (Postcondition, condition [,message]);
9446 -- Invariant_Procedure (_Result) ...
9447 -- Invariant_Procedure (Arg1)
9451 -- First we deal with the postconditions in the body
9453 if Is_Non_Empty_List (Declarations (N)) then
9455 -- Loop through declarations
9457 Prag := First (Declarations (N));
9458 while Present (Prag) loop
9459 if Nkind (Prag) = N_Pragma then
9461 -- If pragma, capture if enabled postcondition, else ignore
9463 if Pragma_Name (Prag) = Name_Postcondition
9464 and then Check_Enabled (Name_Postcondition)
9466 if Plist = No_List then
9467 Plist := Empty_List;
9472 -- If expansion is disabled, as in a generic unit, save
9473 -- pragma for later expansion.
9475 if not Expander_Active then
9476 Prepend (Grab_PPC, Declarations (N));
9478 Append (Grab_PPC, Plist);
9484 -- Not a pragma, if comes from source, then end scan
9486 elsif Comes_From_Source (Prag) then
9489 -- Skip stuff not coming from source
9497 -- Now deal with any postconditions from the spec
9499 if Present (Spec_Id) then
9500 Spec_Postconditions : declare
9501 procedure Process_Post_Conditions
9504 -- This processes the Spec_PPC_List from Spec, processing any
9505 -- postconditions from the list. If Class is True, then only
9506 -- postconditions marked with Class_Present are considered.
9507 -- The caller has checked that Spec_PPC_List is non-Empty.
9509 -----------------------------
9510 -- Process_Post_Conditions --
9511 -----------------------------
9513 procedure Process_Post_Conditions
9526 -- Loop through PPC pragmas from spec
9528 Prag := Spec_PPC_List (Contract (Spec));
9530 if Pragma_Name (Prag) = Name_Postcondition
9531 and then (not Class or else Class_Present (Prag))
9533 if Plist = No_List then
9534 Plist := Empty_List;
9537 if not Expander_Active then
9539 (Grab_PPC (Pspec), Declarations (N));
9541 Append (Grab_PPC (Pspec), Plist);
9545 Prag := Next_Pragma (Prag);
9546 exit when No (Prag);
9548 end Process_Post_Conditions;
9550 -- Start of processing for Spec_Postconditions
9553 if Present (Spec_PPC_List (Contract (Spec_Id))) then
9554 Process_Post_Conditions (Spec_Id, Class => False);
9557 -- Process inherited postconditions
9559 for J in Inherited'Range loop
9560 if Present (Spec_PPC_List (Contract (Inherited (J)))) then
9561 Process_Post_Conditions (Inherited (J), Class => True);
9564 end Spec_Postconditions;
9567 -- If we had any postconditions and expansion is enabled, or if the
9568 -- procedure has invariants, then build the _Postconditions procedure.
9570 if (Present (Plist) or else Invariants_Or_Predicates_Present)
9571 and then Expander_Active
9574 Plist := Empty_List;
9577 -- Special processing for function case
9579 if Ekind (Designator) /= E_Procedure then
9581 Rent : constant Entity_Id :=
9582 Make_Defining_Identifier (Loc,
9583 Chars => Name_uResult);
9584 Ftyp : constant Entity_Id := Etype (Designator);
9587 Set_Etype (Rent, Ftyp);
9589 -- Add argument for return
9593 Make_Parameter_Specification (Loc,
9594 Parameter_Type => New_Occurrence_Of (Ftyp, Loc),
9595 Defining_Identifier => Rent));
9597 -- Add invariant call if returning type with invariants
9599 if Has_Invariants (Etype (Rent))
9600 and then Present (Invariant_Procedure (Etype (Rent)))
9603 Make_Invariant_Call (New_Occurrence_Of (Rent, Loc)));
9607 -- Procedure rather than a function
9613 -- Add invariant calls and predicate calls for parameters. Note that
9614 -- this is done for functions as well, since in Ada 2012 they can
9615 -- have IN OUT args.
9622 Formal := First_Formal (Designator);
9623 while Present (Formal) loop
9624 if Ekind (Formal) /= E_In_Parameter then
9625 Ftype := Etype (Formal);
9627 if Has_Invariants (Ftype)
9628 and then Present (Invariant_Procedure (Ftype))
9632 (New_Occurrence_Of (Formal, Loc)));
9635 if Present (Predicate_Function (Ftype)) then
9637 Make_Predicate_Check
9638 (Ftype, New_Occurrence_Of (Formal, Loc)));
9642 Next_Formal (Formal);
9646 -- Build and insert postcondition procedure
9649 Post_Proc : constant Entity_Id :=
9650 Make_Defining_Identifier (Loc,
9651 Chars => Name_uPostconditions);
9652 -- The entity for the _Postconditions procedure
9655 Prepend_To (Declarations (N),
9656 Make_Subprogram_Body (Loc,
9658 Make_Procedure_Specification (Loc,
9659 Defining_Unit_Name => Post_Proc,
9660 Parameter_Specifications => Parms),
9662 Declarations => Empty_List,
9664 Handled_Statement_Sequence =>
9665 Make_Handled_Sequence_Of_Statements (Loc,
9666 Statements => Plist)));
9668 Set_Ekind (Post_Proc, E_Procedure);
9670 -- If this is a procedure, set the Postcondition_Proc attribute on
9671 -- the proper defining entity for the subprogram.
9673 if Ekind (Designator) = E_Procedure then
9674 Set_Postcondition_Proc (Designator, Post_Proc);
9678 Set_Has_Postconditions (Designator);
9682 ----------------------------
9683 -- Reference_Body_Formals --
9684 ----------------------------
9686 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
9691 if Error_Posted (Spec) then
9695 -- Iterate over both lists. They may be of different lengths if the two
9696 -- specs are not conformant.
9698 Fs := First_Formal (Spec);
9699 Fb := First_Formal (Bod);
9700 while Present (Fs) and then Present (Fb) loop
9701 Generate_Reference (Fs, Fb, 'b');
9704 Style.Check_Identifier (Fb, Fs);
9707 Set_Spec_Entity (Fb, Fs);
9708 Set_Referenced (Fs, False);
9712 end Reference_Body_Formals;
9714 -------------------------
9715 -- Set_Actual_Subtypes --
9716 -------------------------
9718 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
9722 First_Stmt : Node_Id := Empty;
9723 AS_Needed : Boolean;
9726 -- If this is an empty initialization procedure, no need to create
9727 -- actual subtypes (small optimization).
9729 if Ekind (Subp) = E_Procedure
9730 and then Is_Null_Init_Proc (Subp)
9735 Formal := First_Formal (Subp);
9736 while Present (Formal) loop
9737 T := Etype (Formal);
9739 -- We never need an actual subtype for a constrained formal
9741 if Is_Constrained (T) then
9744 -- If we have unknown discriminants, then we do not need an actual
9745 -- subtype, or more accurately we cannot figure it out! Note that
9746 -- all class-wide types have unknown discriminants.
9748 elsif Has_Unknown_Discriminants (T) then
9751 -- At this stage we have an unconstrained type that may need an
9752 -- actual subtype. For sure the actual subtype is needed if we have
9753 -- an unconstrained array type.
9755 elsif Is_Array_Type (T) then
9758 -- The only other case needing an actual subtype is an unconstrained
9759 -- record type which is an IN parameter (we cannot generate actual
9760 -- subtypes for the OUT or IN OUT case, since an assignment can
9761 -- change the discriminant values. However we exclude the case of
9762 -- initialization procedures, since discriminants are handled very
9763 -- specially in this context, see the section entitled "Handling of
9764 -- Discriminants" in Einfo.
9766 -- We also exclude the case of Discrim_SO_Functions (functions used
9767 -- in front end layout mode for size/offset values), since in such
9768 -- functions only discriminants are referenced, and not only are such
9769 -- subtypes not needed, but they cannot always be generated, because
9770 -- of order of elaboration issues.
9772 elsif Is_Record_Type (T)
9773 and then Ekind (Formal) = E_In_Parameter
9774 and then Chars (Formal) /= Name_uInit
9775 and then not Is_Unchecked_Union (T)
9776 and then not Is_Discrim_SO_Function (Subp)
9780 -- All other cases do not need an actual subtype
9786 -- Generate actual subtypes for unconstrained arrays and
9787 -- unconstrained discriminated records.
9790 if Nkind (N) = N_Accept_Statement then
9792 -- If expansion is active, the formal is replaced by a local
9793 -- variable that renames the corresponding entry of the
9794 -- parameter block, and it is this local variable that may
9795 -- require an actual subtype.
9797 if Full_Expander_Active then
9798 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
9800 Decl := Build_Actual_Subtype (T, Formal);
9803 if Present (Handled_Statement_Sequence (N)) then
9805 First (Statements (Handled_Statement_Sequence (N)));
9806 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
9807 Mark_Rewrite_Insertion (Decl);
9809 -- If the accept statement has no body, there will be no
9810 -- reference to the actuals, so no need to compute actual
9817 Decl := Build_Actual_Subtype (T, Formal);
9818 Prepend (Decl, Declarations (N));
9819 Mark_Rewrite_Insertion (Decl);
9822 -- The declaration uses the bounds of an existing object, and
9823 -- therefore needs no constraint checks.
9825 Analyze (Decl, Suppress => All_Checks);
9827 -- We need to freeze manually the generated type when it is
9828 -- inserted anywhere else than in a declarative part.
9830 if Present (First_Stmt) then
9831 Insert_List_Before_And_Analyze (First_Stmt,
9832 Freeze_Entity (Defining_Identifier (Decl), N));
9835 if Nkind (N) = N_Accept_Statement
9836 and then Full_Expander_Active
9838 Set_Actual_Subtype (Renamed_Object (Formal),
9839 Defining_Identifier (Decl));
9841 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
9845 Next_Formal (Formal);
9847 end Set_Actual_Subtypes;
9849 ---------------------
9850 -- Set_Formal_Mode --
9851 ---------------------
9853 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
9854 Spec : constant Node_Id := Parent (Formal_Id);
9857 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
9858 -- since we ensure that corresponding actuals are always valid at the
9859 -- point of the call.
9861 if Out_Present (Spec) then
9862 if Ekind (Scope (Formal_Id)) = E_Function
9863 or else Ekind (Scope (Formal_Id)) = E_Generic_Function
9865 -- [IN] OUT parameters allowed for functions in Ada 2012
9867 if Ada_Version >= Ada_2012 then
9868 if In_Present (Spec) then
9869 Set_Ekind (Formal_Id, E_In_Out_Parameter);
9871 Set_Ekind (Formal_Id, E_Out_Parameter);
9874 -- But not in earlier versions of Ada
9877 Error_Msg_N ("functions can only have IN parameters", Spec);
9878 Set_Ekind (Formal_Id, E_In_Parameter);
9881 elsif In_Present (Spec) then
9882 Set_Ekind (Formal_Id, E_In_Out_Parameter);
9885 Set_Ekind (Formal_Id, E_Out_Parameter);
9886 Set_Never_Set_In_Source (Formal_Id, True);
9887 Set_Is_True_Constant (Formal_Id, False);
9888 Set_Current_Value (Formal_Id, Empty);
9892 Set_Ekind (Formal_Id, E_In_Parameter);
9895 -- Set Is_Known_Non_Null for access parameters since the language
9896 -- guarantees that access parameters are always non-null. We also set
9897 -- Can_Never_Be_Null, since there is no way to change the value.
9899 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
9901 -- Ada 2005 (AI-231): In Ada95, access parameters are always non-
9902 -- null; In Ada 2005, only if then null_exclusion is explicit.
9904 if Ada_Version < Ada_2005
9905 or else Can_Never_Be_Null (Etype (Formal_Id))
9907 Set_Is_Known_Non_Null (Formal_Id);
9908 Set_Can_Never_Be_Null (Formal_Id);
9911 -- Ada 2005 (AI-231): Null-exclusion access subtype
9913 elsif Is_Access_Type (Etype (Formal_Id))
9914 and then Can_Never_Be_Null (Etype (Formal_Id))
9916 Set_Is_Known_Non_Null (Formal_Id);
9919 Set_Mechanism (Formal_Id, Default_Mechanism);
9920 Set_Formal_Validity (Formal_Id);
9921 end Set_Formal_Mode;
9923 -------------------------
9924 -- Set_Formal_Validity --
9925 -------------------------
9927 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
9929 -- If no validity checking, then we cannot assume anything about the
9930 -- validity of parameters, since we do not know there is any checking
9931 -- of the validity on the call side.
9933 if not Validity_Checks_On then
9936 -- If validity checking for parameters is enabled, this means we are
9937 -- not supposed to make any assumptions about argument values.
9939 elsif Validity_Check_Parameters then
9942 -- If we are checking in parameters, we will assume that the caller is
9943 -- also checking parameters, so we can assume the parameter is valid.
9945 elsif Ekind (Formal_Id) = E_In_Parameter
9946 and then Validity_Check_In_Params
9948 Set_Is_Known_Valid (Formal_Id, True);
9950 -- Similar treatment for IN OUT parameters
9952 elsif Ekind (Formal_Id) = E_In_Out_Parameter
9953 and then Validity_Check_In_Out_Params
9955 Set_Is_Known_Valid (Formal_Id, True);
9957 end Set_Formal_Validity;
9959 ------------------------
9960 -- Subtype_Conformant --
9961 ------------------------
9963 function Subtype_Conformant
9964 (New_Id : Entity_Id;
9966 Skip_Controlling_Formals : Boolean := False) return Boolean
9970 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
9971 Skip_Controlling_Formals => Skip_Controlling_Formals);
9973 end Subtype_Conformant;
9975 ---------------------
9976 -- Type_Conformant --
9977 ---------------------
9979 function Type_Conformant
9980 (New_Id : Entity_Id;
9982 Skip_Controlling_Formals : Boolean := False) return Boolean
9986 May_Hide_Profile := False;
9989 (New_Id, Old_Id, Type_Conformant, False, Result,
9990 Skip_Controlling_Formals => Skip_Controlling_Formals);
9992 end Type_Conformant;
9994 -------------------------------
9995 -- Valid_Operator_Definition --
9996 -------------------------------
9998 procedure Valid_Operator_Definition (Designator : Entity_Id) is
10001 Id : constant Name_Id := Chars (Designator);
10005 F := First_Formal (Designator);
10006 while Present (F) loop
10009 if Present (Default_Value (F)) then
10011 ("default values not allowed for operator parameters",
10018 -- Verify that user-defined operators have proper number of arguments
10019 -- First case of operators which can only be unary
10021 if Id = Name_Op_Not
10022 or else Id = Name_Op_Abs
10026 -- Case of operators which can be unary or binary
10028 elsif Id = Name_Op_Add
10029 or Id = Name_Op_Subtract
10031 N_OK := (N in 1 .. 2);
10033 -- All other operators can only be binary
10041 ("incorrect number of arguments for operator", Designator);
10045 and then Base_Type (Etype (Designator)) = Standard_Boolean
10046 and then not Is_Intrinsic_Subprogram (Designator)
10049 ("explicit definition of inequality not allowed", Designator);
10051 end Valid_Operator_Definition;
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