1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2020, 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 pragma Style_Checks
(All_Checks
);
27 -- Turn off subprogram body ordering check. Subprograms are in order by RM
28 -- section rather than alphabetical.
33 -- Local subprograms, used only in this chapter
35 function P_Accept_Alternative
return Node_Id
;
36 function P_Delay_Alternative
return Node_Id
;
37 function P_Delay_Relative_Statement
return Node_Id
;
38 function P_Delay_Until_Statement
return Node_Id
;
39 function P_Entry_Barrier
return Node_Id
;
40 function P_Entry_Body_Formal_Part
return Node_Id
;
41 function P_Entry_Declaration
return Node_Id
;
42 function P_Entry_Index_Specification
return Node_Id
;
43 function P_Protected_Definition
return Node_Id
;
44 function P_Protected_Operation_Declaration_Opt
return Node_Id
;
45 function P_Protected_Operation_Items
return List_Id
;
46 function P_Task_Items
return List_Id
;
47 function P_Task_Definition
return Node_Id
;
49 -----------------------------
50 -- 9.1 Task (also 10.1.3) --
51 -----------------------------
53 -- TASK_TYPE_DECLARATION ::=
54 -- task type DEFINING_IDENTIFIER [KNOWN_DISCRIMINANT_PART]
55 -- [ASPECT_SPECIFICATIONS]
56 -- [is [new INTERFACE_LIST with] TASK_DEFINITION];
58 -- SINGLE_TASK_DECLARATION ::=
59 -- task DEFINING_IDENTIFIER
60 -- [ASPECT_SPECIFICATIONS]
61 -- [is [new INTERFACE_LIST with] TASK_DEFINITION];
64 -- task body DEFINING_IDENTIFIER [ASPECT_SPECIFICATIONS] is
67 -- HANDLED_SEQUENCE_OF_STATEMENTS
68 -- end [task_IDENTIFIER]
71 -- task body DEFINING_IDENTIFIER is separate
72 -- [ASPECT_SPECIFICATIONS];
74 -- This routine scans out a task declaration, task body, or task stub
76 -- The caller has checked that the initial token is TASK and scanned
77 -- past it, so that Token is set to the token after TASK
79 -- Error recovery: cannot raise Error_Resync
81 function P_Task
return Node_Id
is
82 Aspect_Sloc
: Source_Ptr
:= No_Location
;
85 Task_Sloc
: Source_Ptr
;
87 Dummy_Node
: constant Node_Id
:= New_Node
(N_Task_Body
, Token_Ptr
);
88 -- Placeholder node used to hold legal or prematurely declared aspect
89 -- specifications. Depending on the context, the aspect specifications
90 -- may be moved to a new node.
94 Scopes
(Scope
.Last
).Etyp
:= E_Name
;
95 Scopes
(Scope
.Last
).Ecol
:= Start_Column
;
96 Scopes
(Scope
.Last
).Sloc
:= Token_Ptr
;
97 Scopes
(Scope
.Last
).Lreq
:= False;
98 Task_Sloc
:= Prev_Token_Ptr
;
100 if Token
= Tok_Body
then
102 Name_Node
:= P_Defining_Identifier
(C_Is
);
103 Scopes
(Scope
.Last
).Labl
:= Name_Node
;
104 Current_Node
:= Name_Node
;
106 if Token
= Tok_Left_Paren
then
107 Error_Msg_SC
("discriminant part not allowed in task body");
108 Discard_Junk_List
(P_Known_Discriminant_Part_Opt
);
111 if Aspect_Specifications_Present
then
112 Aspect_Sloc
:= Token_Ptr
;
113 P_Aspect_Specifications
(Dummy_Node
, Semicolon
=> False);
120 if Token
= Tok_Separate
then
121 Scan
; -- past SEPARATE
122 Task_Node
:= New_Node
(N_Task_Body_Stub
, Task_Sloc
);
123 Set_Defining_Identifier
(Task_Node
, Name_Node
);
125 if Has_Aspects
(Dummy_Node
) then
127 ("aspect specifications must come after SEPARATE",
131 P_Aspect_Specifications
(Task_Node
, Semicolon
=> False);
133 Pop_Scope_Stack
; -- remove unused entry
138 Task_Node
:= New_Node
(N_Task_Body
, Task_Sloc
);
139 Set_Defining_Identifier
(Task_Node
, Name_Node
);
141 -- Move the aspect specifications to the body node
143 if Has_Aspects
(Dummy_Node
) then
144 Move_Aspects
(From
=> Dummy_Node
, To
=> Task_Node
);
147 Parse_Decls_Begin_End
(Task_Node
);
149 -- The statement list of a task body needs to include at least a
150 -- null statement, so if a parsing error produces an empty list,
153 if No
(First
(Statements
154 (Handled_Statement_Sequence
(Task_Node
))))
156 Set_Statements
(Handled_Statement_Sequence
(Task_Node
),
157 New_List
(Make_Null_Statement
(Token_Ptr
)));
163 -- Otherwise we must have a task declaration
166 if Token
= Tok_Type
then
168 Task_Node
:= New_Node
(N_Task_Type_Declaration
, Task_Sloc
);
169 Name_Node
:= P_Defining_Identifier
;
170 Set_Defining_Identifier
(Task_Node
, Name_Node
);
171 Scopes
(Scope
.Last
).Labl
:= Name_Node
;
172 Current_Node
:= Name_Node
;
173 Set_Discriminant_Specifications
174 (Task_Node
, P_Known_Discriminant_Part_Opt
);
177 Task_Node
:= New_Node
(N_Single_Task_Declaration
, Task_Sloc
);
178 Name_Node
:= P_Defining_Identifier
(C_Is
);
179 Set_Defining_Identifier
(Task_Node
, Name_Node
);
180 Scopes
(Scope
.Last
).Labl
:= Name_Node
;
181 Current_Node
:= Name_Node
;
183 if Token
= Tok_Left_Paren
then
184 Error_Msg_SC
("discriminant part not allowed for single task");
185 Discard_Junk_List
(P_Known_Discriminant_Part_Opt
);
189 -- Scan aspect specifications, don't eat the semicolon, since it
190 -- might not be there if we have an IS.
192 P_Aspect_Specifications
(Task_Node
, Semicolon
=> False);
194 -- Parse optional task definition. Note that P_Task_Definition scans
195 -- out the semicolon and possible aspect specifications as well as
196 -- the task definition itself.
198 if Token
= Tok_Semicolon
then
200 -- A little check, if the next token after semicolon is Entry,
201 -- then surely the semicolon should really be IS
203 Scan
; -- past semicolon
205 if Token
= Tok_Entry
then
206 Error_Msg_SP
-- CODEFIX
207 ("|"";"" should be IS");
208 Set_Task_Definition
(Task_Node
, P_Task_Definition
);
210 Pop_Scope_Stack
; -- Remove unused entry
213 -- Here we have a task definition
216 TF_Is
; -- must have IS if no semicolon
220 if Token
= Tok_New
then
223 Error_Msg_Ada_2005_Extension
("task interface");
225 Set_Interface_List
(Task_Node
, New_List
);
228 Append
(P_Qualified_Simple_Name
, Interface_List
(Task_Node
));
229 exit when Token
/= Tok_And
;
233 if Token
/= Tok_With
then
234 Error_Msg_SC
-- CODEFIX
240 if Token
= Tok_Private
then
241 Error_Msg_SP
-- CODEFIX
242 ("PRIVATE not allowed in task type declaration");
246 Set_Task_Definition
(Task_Node
, P_Task_Definition
);
253 --------------------------------
254 -- 9.1 Task Type Declaration --
255 --------------------------------
257 -- Parsed by P_Task (9.1)
259 ----------------------------------
260 -- 9.1 Single Task Declaration --
261 ----------------------------------
263 -- Parsed by P_Task (9.1)
265 --------------------------
266 -- 9.1 Task Definition --
267 --------------------------
269 -- TASK_DEFINITION ::=
273 -- end [task_IDENTIFIER];
275 -- The caller has already made the scope stack entry
277 -- Note: there is a small deviation from official syntax here in that we
278 -- regard the semicolon after end as part of the Task_Definition, and in
279 -- the official syntax, it's part of the enclosing declaration. The reason
280 -- for this deviation is that otherwise the end processing would have to
281 -- be special cased, which would be a nuisance.
283 -- Error recovery: cannot raise Error_Resync
285 function P_Task_Definition
return Node_Id
is
289 Def_Node
:= New_Node
(N_Task_Definition
, Token_Ptr
);
290 Set_Visible_Declarations
(Def_Node
, P_Task_Items
);
292 if Token
= Tok_Private
then
293 Scan
; -- past PRIVATE
294 Set_Private_Declarations
(Def_Node
, P_Task_Items
);
296 -- Deal gracefully with multiple PRIVATE parts
298 while Token
= Tok_Private
loop
299 Error_Msg_SC
("only one private part allowed per task");
300 Scan
; -- past PRIVATE
301 Append_List
(P_Task_Items
, Private_Declarations
(Def_Node
));
305 End_Statements
(Def_Node
);
307 end P_Task_Definition
;
313 -- TASK_ITEM ::= ENTRY_DECLARATION | REPRESENTATION_CLAUSE
315 -- This subprogram scans a (possibly empty) list of task items and pragmas
317 -- Error recovery: cannot raise Error_Resync
319 -- Note: a pragma can also be returned in this position
321 function P_Task_Items
return List_Id
is
324 Decl_Sloc
: Source_Ptr
;
327 -- Get rid of active SIS entry from outer scope. This means we will
328 -- miss some nested cases, but it doesn't seem worth the effort. See
329 -- discussion in Par for further details
331 SIS_Entry_Active
:= False;
333 -- Loop to scan out task items
338 Decl_Sloc
:= Token_Ptr
;
340 if Token
= Tok_Pragma
then
341 P_Pragmas_Opt
(Items
);
343 -- Ada 2005 (AI-397): Reserved words NOT and OVERRIDING may begin an
344 -- entry declaration.
346 elsif Token
= Tok_Entry
347 or else Token
= Tok_Not
348 or else Token
= Tok_Overriding
350 Append
(P_Entry_Declaration
, Items
);
352 elsif Token
= Tok_For
then
354 -- Representation clause in task declaration. The only rep clause
355 -- which is legal in a protected declaration is an address clause,
356 -- so that is what we try to scan out.
358 Item_Node
:= P_Representation_Clause
;
360 if Nkind
(Item_Node
) = N_At_Clause
then
361 Append
(Item_Node
, Items
);
363 elsif Nkind
(Item_Node
) = N_Attribute_Definition_Clause
364 and then Chars
(Item_Node
) = Name_Address
366 Append
(Item_Node
, Items
);
370 ("the only representation clause " &
371 "allowed here is an address clause!", Decl_Sloc
);
374 elsif Token
= Tok_Identifier
375 or else Token
in Token_Class_Declk
377 Error_Msg_SC
("illegal declaration in task definition");
378 Resync_Past_Semicolon
;
392 -- Parsed by P_Task (9.1)
394 ----------------------------------
395 -- 9.4 Protected (also 10.1.3) --
396 ----------------------------------
398 -- PROTECTED_TYPE_DECLARATION ::=
399 -- protected type DEFINING_IDENTIFIER [KNOWN_DISCRIMINANT_PART]
400 -- [ASPECT_SPECIFICATIONS]
401 -- is [new INTERFACE_LIST with] PROTECTED_DEFINITION;
403 -- SINGLE_PROTECTED_DECLARATION ::=
404 -- protected DEFINING_IDENTIFIER
405 -- [ASPECT_SPECIFICATIONS]
406 -- is [new INTERFACE_LIST with] PROTECTED_DEFINITION;
408 -- PROTECTED_BODY ::=
409 -- protected body DEFINING_IDENTIFIER
410 -- [ASPECT_SPECIFICATIONS]
412 -- {PROTECTED_OPERATION_ITEM}
413 -- end [protected_IDENTIFIER];
415 -- PROTECTED_BODY_STUB ::=
416 -- protected body DEFINING_IDENTIFIER is separate
417 -- [ASPECT_SPECIFICATIONS];
419 -- This routine scans out a protected declaration, protected body
420 -- or a protected stub.
422 -- The caller has checked that the initial token is PROTECTED and
423 -- scanned past it, so Token is set to the following token.
425 -- Error recovery: cannot raise Error_Resync
427 function P_Protected
return Node_Id
is
428 Aspect_Sloc
: Source_Ptr
:= No_Location
;
430 Protected_Node
: Node_Id
;
431 Protected_Sloc
: Source_Ptr
;
432 Scan_State
: Saved_Scan_State
;
434 Dummy_Node
: constant Node_Id
:= New_Node
(N_Protected_Body
, Token_Ptr
);
435 -- Placeholder node used to hold legal or prematurely declared aspect
436 -- specifications. Depending on the context, the aspect specifications
437 -- may be moved to a new node.
441 Scopes
(Scope
.Last
).Etyp
:= E_Name
;
442 Scopes
(Scope
.Last
).Ecol
:= Start_Column
;
443 Scopes
(Scope
.Last
).Lreq
:= False;
444 Protected_Sloc
:= Prev_Token_Ptr
;
446 if Token
= Tok_Body
then
448 Name_Node
:= P_Defining_Identifier
(C_Is
);
449 Scopes
(Scope
.Last
).Labl
:= Name_Node
;
450 Current_Node
:= Name_Node
;
452 if Token
= Tok_Left_Paren
then
453 Error_Msg_SC
("discriminant part not allowed in protected body");
454 Discard_Junk_List
(P_Known_Discriminant_Part_Opt
);
457 if Aspect_Specifications_Present
then
458 Aspect_Sloc
:= Token_Ptr
;
459 P_Aspect_Specifications
(Dummy_Node
, Semicolon
=> False);
466 if Token
= Tok_Separate
then
467 Scan
; -- past SEPARATE
469 Protected_Node
:= New_Node
(N_Protected_Body_Stub
, Protected_Sloc
);
470 Set_Defining_Identifier
(Protected_Node
, Name_Node
);
472 if Has_Aspects
(Dummy_Node
) then
474 ("aspect specifications must come after SEPARATE",
478 P_Aspect_Specifications
(Protected_Node
, Semicolon
=> False);
480 Pop_Scope_Stack
; -- remove unused entry
485 Protected_Node
:= New_Node
(N_Protected_Body
, Protected_Sloc
);
486 Set_Defining_Identifier
(Protected_Node
, Name_Node
);
488 Move_Aspects
(From
=> Dummy_Node
, To
=> Protected_Node
);
489 Set_Declarations
(Protected_Node
, P_Protected_Operation_Items
);
490 End_Statements
(Protected_Node
);
493 return Protected_Node
;
495 -- Otherwise we must have a protected declaration
498 if Token
= Tok_Type
then
501 New_Node
(N_Protected_Type_Declaration
, Protected_Sloc
);
502 Name_Node
:= P_Defining_Identifier
(C_Is
);
503 Set_Defining_Identifier
(Protected_Node
, Name_Node
);
504 Scopes
(Scope
.Last
).Labl
:= Name_Node
;
505 Current_Node
:= Name_Node
;
506 Set_Discriminant_Specifications
507 (Protected_Node
, P_Known_Discriminant_Part_Opt
);
511 New_Node
(N_Single_Protected_Declaration
, Protected_Sloc
);
512 Name_Node
:= P_Defining_Identifier
(C_Is
);
513 Set_Defining_Identifier
(Protected_Node
, Name_Node
);
515 if Token
= Tok_Left_Paren
then
517 ("discriminant part not allowed for single protected");
518 Discard_Junk_List
(P_Known_Discriminant_Part_Opt
);
521 Scopes
(Scope
.Last
).Labl
:= Name_Node
;
522 Current_Node
:= Name_Node
;
525 P_Aspect_Specifications
(Protected_Node
, Semicolon
=> False);
527 -- Check for semicolon not followed by IS, this is something like
533 -- protected type r IS END;
535 if Token
= Tok_Semicolon
then
536 Save_Scan_State
(Scan_State
); -- at semicolon
537 Scan
; -- past semicolon
539 if Token
/= Tok_Is
then
540 Restore_Scan_State
(Scan_State
);
541 Error_Msg_SC
-- CODEFIX
543 Set_Protected_Definition
(Protected_Node
,
544 Make_Protected_Definition
(Token_Ptr
,
545 Visible_Declarations
=> Empty_List
,
546 End_Label
=> Empty
));
548 SIS_Entry_Active
:= False;
550 (Protected_Definition
(Protected_Node
), Protected_Node
);
551 return Protected_Node
;
554 Error_Msg_SP
-- CODEFIX
555 ("|extra ""("" ignored");
562 if Token
= Tok_New
then
565 Error_Msg_Ada_2005_Extension
("protected interface");
567 Set_Interface_List
(Protected_Node
, New_List
);
570 Append
(P_Qualified_Simple_Name
,
571 Interface_List
(Protected_Node
));
573 exit when Token
/= Tok_And
;
577 if Token
/= Tok_With
then
578 Error_Msg_SC
-- CODEFIX
585 Set_Protected_Definition
(Protected_Node
, P_Protected_Definition
);
586 return Protected_Node
;
590 -------------------------------------
591 -- 9.4 Protected Type Declaration --
592 -------------------------------------
594 -- Parsed by P_Protected (9.4)
596 ---------------------------------------
597 -- 9.4 Single Protected Declaration --
598 ---------------------------------------
600 -- Parsed by P_Protected (9.4)
602 -------------------------------
603 -- 9.4 Protected Definition --
604 -------------------------------
606 -- PROTECTED_DEFINITION ::=
607 -- {PROTECTED_OPERATION_DECLARATION}
609 -- {PROTECTED_ELEMENT_DECLARATION}]
610 -- end [protected_IDENTIFIER]
612 -- PROTECTED_ELEMENT_DECLARATION ::=
613 -- PROTECTED_OPERATION_DECLARATION
614 -- | COMPONENT_DECLARATION
616 -- The caller has already established the scope stack entry
618 -- Error recovery: cannot raise Error_Resync
620 function P_Protected_Definition
return Node_Id
is
623 Priv_Decls
: List_Id
;
627 Def_Node
:= New_Node
(N_Protected_Definition
, Token_Ptr
);
629 -- Get rid of active SIS entry from outer scope. This means we will
630 -- miss some nested cases, but it doesn't seem worth the effort. See
631 -- discussion in Par for further details
633 SIS_Entry_Active
:= False;
635 -- Loop to scan visible declarations (protected operation declarations)
637 Vis_Decls
:= New_List
;
638 Set_Visible_Declarations
(Def_Node
, Vis_Decls
);
640 -- Flag and discard all pragmas which cannot appear in the protected
641 -- definition. Note that certain pragmas are still allowed as long as
642 -- they apply to entries, entry families, or protected subprograms.
644 P_Pragmas_Opt
(Vis_Decls
);
647 Item_Node
:= P_Protected_Operation_Declaration_Opt
;
649 if Present
(Item_Node
) then
650 Append
(Item_Node
, Vis_Decls
);
653 P_Pragmas_Opt
(Vis_Decls
);
655 exit when No
(Item_Node
);
658 -- Deal with PRIVATE part (including graceful handling of multiple
661 Private_Loop
: while Token
= Tok_Private
loop
662 Priv_Decls
:= Private_Declarations
(Def_Node
);
664 if Present
(Priv_Decls
) then
665 Error_Msg_SC
("duplicate private part");
667 Priv_Decls
:= New_List
;
668 Set_Private_Declarations
(Def_Node
, Priv_Decls
);
671 Scan
; -- past PRIVATE
673 -- Flag and discard all pragmas which cannot appear in the protected
674 -- definition. Note that certain pragmas are still allowed as long as
675 -- they apply to entries, entry families, or protected subprograms.
677 P_Pragmas_Opt
(Priv_Decls
);
679 Declaration_Loop
: loop
680 if Token
= Tok_Identifier
then
681 P_Component_Items
(Priv_Decls
);
682 P_Pragmas_Opt
(Priv_Decls
);
685 Item_Node
:= P_Protected_Operation_Declaration_Opt
;
687 if Present
(Item_Node
) then
688 Append
(Item_Node
, Priv_Decls
);
691 P_Pragmas_Opt
(Priv_Decls
);
693 exit Declaration_Loop
when No
(Item_Node
);
695 end loop Declaration_Loop
;
696 end loop Private_Loop
;
698 End_Statements
(Def_Node
);
700 end P_Protected_Definition
;
702 ------------------------------------------
703 -- 9.4 Protected Operation Declaration --
704 ------------------------------------------
706 -- PROTECTED_OPERATION_DECLARATION ::=
707 -- SUBPROGRAM_DECLARATION
708 -- | ENTRY_DECLARATION
709 -- | REPRESENTATION_CLAUSE
711 -- Error recovery: cannot raise Error_Resync
713 -- Note: a pragma can also be returned in this position
715 -- We are not currently permitting representation clauses to appear as
716 -- protected operation declarations, do we have to rethink this???
718 function P_Protected_Operation_Declaration_Opt
return Node_Id
is
722 function P_Entry_Or_Subprogram_With_Indicator
return Node_Id
;
723 -- Ada 2005 (AI-397): Parse an entry or a subprogram with an overriding
724 -- indicator. The caller has checked that the initial token is NOT or
727 ------------------------------------------
728 -- P_Entry_Or_Subprogram_With_Indicator --
729 ------------------------------------------
731 function P_Entry_Or_Subprogram_With_Indicator
return Node_Id
is
732 Decl
: Node_Id
:= Error
;
733 Is_Overriding
: Boolean := False;
734 Not_Overriding
: Boolean := False;
737 if Token
= Tok_Not
then
740 if Token
= Tok_Overriding
then
741 Scan
; -- past OVERRIDING
742 Not_Overriding
:= True;
744 Error_Msg_SC
-- CODEFIX
745 ("OVERRIDING expected!");
749 Scan
; -- past OVERRIDING
750 Is_Overriding
:= True;
753 if Is_Overriding
or else Not_Overriding
then
754 if Ada_Version
< Ada_2005
then
755 Error_Msg_Ada_2005_Extension
("overriding indicator");
757 elsif Token
= Tok_Entry
then
758 Decl
:= P_Entry_Declaration
;
760 Set_Must_Override
(Decl
, Is_Overriding
);
761 Set_Must_Not_Override
(Decl
, Not_Overriding
);
763 elsif Token
= Tok_Function
or else Token
= Tok_Procedure
then
764 Decl
:= P_Subprogram
(Pf_Decl_Pexp
);
766 Set_Must_Override
(Specification
(Decl
), Is_Overriding
);
767 Set_Must_Not_Override
(Specification
(Decl
), Not_Overriding
);
770 Error_Msg_SC
-- CODEFIX
771 ("ENTRY, FUNCTION or PROCEDURE expected!");
776 end P_Entry_Or_Subprogram_With_Indicator
;
778 Result
: Node_Id
:= Empty
;
780 -- Start of processing for P_Protected_Operation_Declaration_Opt
783 -- This loop runs more than once only when a junk declaration is skipped
794 Result
:= P_Entry_Or_Subprogram_With_Indicator
;
798 Result
:= P_Entry_Declaration
;
804 Result
:= P_Subprogram
(Pf_Decl_Pexp
);
807 when Tok_Identifier
=>
810 Skip_Declaration
(L
);
812 if Nkind
(First
(L
)) = N_Object_Declaration
then
814 ("component must be declared in private part of " &
815 "protected type", P
);
818 ("illegal declaration in protected definition", P
);
824 ("representation clause not allowed in protected definition");
825 Resync_Past_Semicolon
;
829 if Token
in Token_Class_Declk
then
830 Error_Msg_SC
("illegal declaration in protected definition");
831 Resync_Past_Semicolon
;
833 -- Return now to avoid cascaded messages if next declaration
834 -- is a valid component declaration.
843 if Nkind
(Result
) = N_Subprogram_Declaration
844 and then Nkind
(Specification
(Result
)) =
845 N_Procedure_Specification
846 and then Null_Present
(Specification
(Result
))
849 ("protected operation cannot be a null procedure",
850 Null_Statement
(Specification
(Result
)));
854 end P_Protected_Operation_Declaration_Opt
;
856 -----------------------------------
857 -- 9.4 Protected Operation Item --
858 -----------------------------------
860 -- PROTECTED_OPERATION_ITEM ::=
861 -- SUBPROGRAM_DECLARATION
864 -- | REPRESENTATION_CLAUSE
866 -- This procedure parses and returns a list of protected operation items
868 -- We are not currently permitting representation clauses to appear
869 -- as protected operation items, do we have to rethink this???
871 function P_Protected_Operation_Items
return List_Id
is
875 Item_List
:= New_List
;
878 if Token
= Tok_Entry
or else Bad_Spelling_Of
(Tok_Entry
) then
879 Append
(P_Entry_Body
, Item_List
);
881 -- If the operation starts with procedure, function, or an overriding
882 -- indicator ("overriding" or "not overriding"), parse a subprogram.
884 elsif Token
= Tok_Function
or else Bad_Spelling_Of
(Tok_Function
)
886 Token
= Tok_Procedure
or else Bad_Spelling_Of
(Tok_Procedure
)
888 Token
= Tok_Overriding
or else Bad_Spelling_Of
(Tok_Overriding
)
890 Token
= Tok_Not
or else Bad_Spelling_Of
(Tok_Not
)
892 Append
(P_Subprogram
(Pf_Decl_Pbod_Pexp
), Item_List
);
894 elsif Token
= Tok_Pragma
or else Bad_Spelling_Of
(Tok_Pragma
) then
895 P_Pragmas_Opt
(Item_List
);
897 elsif Token
= Tok_Private
or else Bad_Spelling_Of
(Tok_Private
) then
898 Error_Msg_SC
("PRIVATE not allowed in protected body");
899 Scan
; -- past PRIVATE
901 elsif Token
= Tok_Identifier
then
902 Error_Msg_SC
("all components must be declared in spec!");
903 Resync_Past_Semicolon
;
905 elsif Token
in Token_Class_Declk
then
906 Error_Msg_SC
("declaration not allowed in protected body");
907 Resync_Past_Semicolon
;
915 end P_Protected_Operation_Items
;
917 ------------------------------
918 -- 9.5.2 Entry Declaration --
919 ------------------------------
921 -- ENTRY_DECLARATION ::=
922 -- [OVERRIDING_INDICATOR]
923 -- entry DEFINING_IDENTIFIER
924 -- [(DISCRETE_SUBTYPE_DEFINITION)] PARAMETER_PROFILE
925 -- [ASPECT_SPECIFICATIONS];
927 -- The caller has checked that the initial token is ENTRY, NOT or
930 -- Error recovery: cannot raise Error_Resync
932 function P_Entry_Declaration
return Node_Id
is
934 Scan_State
: Saved_Scan_State
;
936 -- Flags for optional overriding indication. Two flags are needed,
937 -- to distinguish positive and negative overriding indicators from
938 -- the absence of any indicator.
940 Is_Overriding
: Boolean := False;
941 Not_Overriding
: Boolean := False;
944 -- Ada 2005 (AI-397): Scan leading overriding indicator
946 if Token
= Tok_Not
then
949 if Token
= Tok_Overriding
then
950 Scan
; -- part OVERRIDING
951 Not_Overriding
:= True;
953 Error_Msg_SC
-- CODEFIX
954 ("OVERRIDING expected!");
957 elsif Token
= Tok_Overriding
then
958 Scan
; -- part OVERRIDING
959 Is_Overriding
:= True;
962 if Is_Overriding
or else Not_Overriding
then
963 if Ada_Version
< Ada_2005
then
964 Error_Msg_Ada_2005_Extension
("overriding indicator");
965 elsif Token
/= Tok_Entry
then
966 Error_Msg_SC
-- CODEFIX
971 Decl_Node
:= New_Node
(N_Entry_Declaration
, Token_Ptr
);
974 Set_Defining_Identifier
975 (Decl_Node
, P_Defining_Identifier
(C_Left_Paren_Semicolon
));
977 -- If left paren, could be (Discrete_Subtype_Definition) or Formal_Part
979 if Token
= Tok_Left_Paren
then
982 -- If identifier after left paren, could still be either
984 if Token
= Tok_Identifier
then
985 Save_Scan_State
(Scan_State
); -- at Id
988 -- If comma or colon after Id, must be Formal_Part
990 if Token
= Tok_Comma
or else Token
= Tok_Colon
then
991 Restore_Scan_State
(Scan_State
); -- to Id
992 Set_Parameter_Specifications
(Decl_Node
, P_Formal_Part
);
994 -- Else if Id without comma or colon, must be discrete subtype
998 Restore_Scan_State
(Scan_State
); -- to Id
999 Set_Discrete_Subtype_Definition
1000 (Decl_Node
, P_Discrete_Subtype_Definition
);
1002 Set_Parameter_Specifications
(Decl_Node
, P_Parameter_Profile
);
1005 -- If no Id, must be discrete subtype definition
1008 Set_Discrete_Subtype_Definition
1009 (Decl_Node
, P_Discrete_Subtype_Definition
);
1011 Set_Parameter_Specifications
(Decl_Node
, P_Parameter_Profile
);
1015 if Is_Overriding
then
1016 Set_Must_Override
(Decl_Node
);
1017 elsif Not_Overriding
then
1018 Set_Must_Not_Override
(Decl_Node
);
1021 -- Error recovery check for illegal return
1023 if Token
= Tok_Return
then
1024 Error_Msg_SC
("entry cannot have return value!");
1026 Discard_Junk_Node
(P_Subtype_Indication
);
1029 -- Error recovery check for improper use of entry barrier in spec
1031 if Token
= Tok_When
then
1032 Error_Msg_SC
("barrier not allowed here (belongs in body)");
1034 Discard_Junk_Node
(P_Expression_No_Right_Paren
);
1037 P_Aspect_Specifications
(Decl_Node
);
1041 when Error_Resync
=>
1042 Resync_Past_Semicolon
;
1044 end P_Entry_Declaration
;
1046 -----------------------------
1047 -- 9.5.2 Accept Statement --
1048 -----------------------------
1050 -- ACCEPT_STATEMENT ::=
1051 -- accept entry_DIRECT_NAME
1052 -- [(ENTRY_INDEX)] PARAMETER_PROFILE [do
1053 -- HANDLED_SEQUENCE_OF_STATEMENTS
1054 -- end [entry_IDENTIFIER]];
1056 -- The caller has checked that the initial token is ACCEPT
1058 -- Error recovery: cannot raise Error_Resync. If an error occurs, the
1059 -- scan is resynchronized past the next semicolon and control returns.
1061 function P_Accept_Statement
return Node_Id
is
1062 Scan_State
: Saved_Scan_State
;
1063 Accept_Node
: Node_Id
;
1068 Scopes
(Scope
.Last
).Sloc
:= Token_Ptr
;
1069 Scopes
(Scope
.Last
).Ecol
:= Start_Column
;
1071 Accept_Node
:= New_Node
(N_Accept_Statement
, Token_Ptr
);
1072 Scan
; -- past ACCEPT
1073 Scopes
(Scope
.Last
).Labl
:= Token_Node
;
1074 Current_Node
:= Token_Node
;
1076 Set_Entry_Direct_Name
(Accept_Node
, P_Identifier
(C_Do
));
1078 -- Left paren could be (Entry_Index) or Formal_Part, determine which
1080 if Token
= Tok_Left_Paren
then
1081 Save_Scan_State
(Scan_State
); -- at left paren
1082 Scan
; -- past left paren
1084 -- If first token after left paren not identifier, then Entry_Index
1086 if Token
/= Tok_Identifier
then
1087 Set_Entry_Index
(Accept_Node
, P_Expression
);
1089 Set_Parameter_Specifications
(Accept_Node
, P_Parameter_Profile
);
1091 -- First token after left paren is identifier, could be either case
1093 else -- Token = Tok_Identifier
1094 Scan
; -- past identifier
1096 -- If identifier followed by comma or colon, must be Formal_Part
1098 if Token
= Tok_Comma
or else Token
= Tok_Colon
then
1099 Restore_Scan_State
(Scan_State
); -- to left paren
1100 Set_Parameter_Specifications
(Accept_Node
, P_Parameter_Profile
);
1102 -- If identifier not followed by comma/colon, must be entry index
1105 Restore_Scan_State
(Scan_State
); -- to left paren
1106 Scan
; -- past left paren (again)
1107 Set_Entry_Index
(Accept_Node
, P_Expression
);
1109 Set_Parameter_Specifications
(Accept_Node
, P_Parameter_Profile
);
1114 -- Scan out DO if present
1116 if Token
= Tok_Do
then
1117 Scopes
(Scope
.Last
).Etyp
:= E_Name
;
1118 Scopes
(Scope
.Last
).Lreq
:= False;
1120 Hand_Seq
:= P_Handled_Sequence_Of_Statements
;
1121 Set_Handled_Statement_Sequence
(Accept_Node
, Hand_Seq
);
1122 End_Statements
(Handled_Statement_Sequence
(Accept_Node
));
1124 -- Exception handlers not allowed in Ada 95 node
1126 if Present
(Exception_Handlers
(Hand_Seq
)) then
1127 if Ada_Version
= Ada_83
then
1129 ("(Ada 83) exception handlers in accept not allowed",
1130 First_Non_Pragma
(Exception_Handlers
(Hand_Seq
)));
1135 Pop_Scope_Stack
; -- discard unused entry
1141 -- If error, resynchronize past semicolon
1144 when Error_Resync
=>
1145 Resync_Past_Semicolon
;
1146 Pop_Scope_Stack
; -- discard unused entry
1148 end P_Accept_Statement
;
1150 ------------------------
1151 -- 9.5.2 Entry Index --
1152 ------------------------
1154 -- Parsed by P_Expression (4.4)
1156 --------------------------
1157 -- 9.5.2 Entry Barrier --
1158 --------------------------
1160 -- ENTRY_BARRIER ::= when CONDITION
1162 -- Error_Recovery: cannot raise Error_Resync
1164 function P_Entry_Barrier
return Node_Id
is
1168 if Token
= Tok_When
then
1170 Bnode
:= P_Expression_No_Right_Paren
;
1172 if Token
= Tok_Colon_Equal
then
1173 Error_Msg_SC
-- CODEFIX
1174 ("|"":="" should be ""=""");
1176 Bnode
:= P_Expression_No_Right_Paren
;
1180 T_When
; -- to give error message
1185 end P_Entry_Barrier
;
1187 -----------------------
1188 -- 9.5.2 Entry Body --
1189 -----------------------
1192 -- entry DEFINING_IDENTIFIER ENTRY_BODY_FORMAL_PART
1193 -- [ASPECT_SPECIFICATIONS] ENTRY_BARRIER
1197 -- HANDLED_SEQUENCE_OF_STATEMENTS
1198 -- end [entry_IDENTIFIER];
1200 -- The caller has checked that the initial token is ENTRY
1202 -- Error_Recovery: cannot raise Error_Resync
1204 function P_Entry_Body
return Node_Id
is
1205 Dummy_Node
: Node_Id
;
1206 Entry_Node
: Node_Id
;
1207 Formal_Part_Node
: Node_Id
;
1208 Name_Node
: Node_Id
;
1212 Entry_Node
:= New_Node
(N_Entry_Body
, Token_Ptr
);
1215 Scopes
(Scope
.Last
).Ecol
:= Start_Column
;
1216 Scopes
(Scope
.Last
).Lreq
:= False;
1217 Scopes
(Scope
.Last
).Etyp
:= E_Name
;
1218 Scopes
(Scope
.Last
).Sloc
:= Token_Ptr
;
1220 Name_Node
:= P_Defining_Identifier
;
1221 Set_Defining_Identifier
(Entry_Node
, Name_Node
);
1222 Scopes
(Scope
.Last
).Labl
:= Name_Node
;
1223 Current_Node
:= Name_Node
;
1225 Formal_Part_Node
:= P_Entry_Body_Formal_Part
;
1226 Set_Entry_Body_Formal_Part
(Entry_Node
, Formal_Part_Node
);
1228 -- Ada 2012 (AI12-0169): Aspect specifications may appear on an entry
1229 -- body immediately after the formal part. Do not parse the aspect
1230 -- specifications directly because the "when" of the entry barrier may
1231 -- be interpreted as a misused "with".
1233 if Token
= Tok_With
then
1234 P_Aspect_Specifications
(Entry_Node
, Semicolon
=> False);
1237 Set_Condition
(Formal_Part_Node
, P_Entry_Barrier
);
1239 -- Detect an illegal placement of aspect specifications following the
1242 -- entry E ... when Barrier with Aspect is
1244 if Token
= Tok_With
then
1245 Error_Msg_SC
("aspect specifications must come before entry barrier");
1247 -- Consume the illegal aspects to allow for parsing to continue
1249 Dummy_Node
:= New_Node
(N_Entry_Body
, Sloc
(Entry_Node
));
1250 P_Aspect_Specifications
(Dummy_Node
, Semicolon
=> False);
1254 Parse_Decls_Begin_End
(Entry_Node
);
1259 -----------------------------------
1260 -- 9.5.2 Entry Body Formal Part --
1261 -----------------------------------
1263 -- ENTRY_BODY_FORMAL_PART ::=
1264 -- [(ENTRY_INDEX_SPECIFICATION)] [PARAMETER_PART]
1266 -- Error_Recovery: cannot raise Error_Resync
1268 function P_Entry_Body_Formal_Part
return Node_Id
is
1269 Fpart_Node
: Node_Id
;
1270 Scan_State
: Saved_Scan_State
;
1273 Fpart_Node
:= New_Node
(N_Entry_Body_Formal_Part
, Token_Ptr
);
1275 -- See if entry index specification present, and if so parse it
1277 if Token
= Tok_Left_Paren
then
1278 Save_Scan_State
(Scan_State
); -- at left paren
1279 Scan
; -- past left paren
1281 if Token
= Tok_For
then
1282 Set_Entry_Index_Specification
1283 (Fpart_Node
, P_Entry_Index_Specification
);
1286 Restore_Scan_State
(Scan_State
); -- to left paren
1289 -- Check for (common?) case of left paren omitted before FOR. This
1290 -- is a tricky case, because the corresponding missing left paren
1291 -- can cause real havoc if a formal part is present which gets
1292 -- treated as part of the discrete subtype definition of the
1293 -- entry index specification, so just give error and resynchronize
1295 elsif Token
= Tok_For
then
1296 T_Left_Paren
; -- to give error message
1300 Set_Parameter_Specifications
(Fpart_Node
, P_Parameter_Profile
);
1302 end P_Entry_Body_Formal_Part
;
1304 --------------------------------------
1305 -- 9.5.2 Entry Index Specification --
1306 --------------------------------------
1308 -- ENTRY_INDEX_SPECIFICATION ::=
1309 -- for DEFINING_IDENTIFIER in DISCRETE_SUBTYPE_DEFINITION
1310 -- [ASPECT_SPECIFICATION]
1312 -- Error recovery: can raise Error_Resync
1314 function P_Entry_Index_Specification
return Node_Id
is
1315 Iterator_Node
: Node_Id
;
1318 Iterator_Node
:= New_Node
(N_Entry_Index_Specification
, Token_Ptr
);
1320 Set_Defining_Identifier
(Iterator_Node
, P_Defining_Identifier
(C_In
));
1322 Set_Discrete_Subtype_Definition
1323 (Iterator_Node
, P_Discrete_Subtype_Definition
);
1325 if Token
= Tok_With
then
1326 P_Aspect_Specifications
(Iterator_Node
, False);
1329 return Iterator_Node
;
1330 end P_Entry_Index_Specification
;
1332 ---------------------------------
1333 -- 9.5.3 Entry Call Statement --
1334 ---------------------------------
1336 -- Parsed by P_Name (4.1). Within a select, an entry call is parsed
1337 -- by P_Select_Statement (9.7)
1339 ------------------------------
1340 -- 9.5.4 Requeue Statement --
1341 ------------------------------
1343 -- REQUEUE_STATEMENT ::= requeue entry_NAME [with abort];
1345 -- The caller has checked that the initial token is requeue
1347 -- Error recovery: can raise Error_Resync
1349 function P_Requeue_Statement
return Node_Id
is
1350 Requeue_Node
: Node_Id
;
1353 Requeue_Node
:= New_Node
(N_Requeue_Statement
, Token_Ptr
);
1354 Scan
; -- past REQUEUE
1355 Set_Name
(Requeue_Node
, P_Name
);
1357 if Token
= Tok_With
then
1360 Set_Abort_Present
(Requeue_Node
, True);
1364 return Requeue_Node
;
1365 end P_Requeue_Statement
;
1367 --------------------------
1368 -- 9.6 Delay Statement --
1369 --------------------------
1371 -- DELAY_STATEMENT ::=
1372 -- DELAY_UNTIL_STATEMENT
1373 -- | DELAY_RELATIVE_STATEMENT
1375 -- The caller has checked that the initial token is DELAY
1377 -- Error recovery: cannot raise Error_Resync
1379 function P_Delay_Statement
return Node_Id
is
1383 -- The following check for delay until misused in Ada 83 doesn't catch
1384 -- all cases, but it's good enough to catch most of them.
1386 if Token_Name
= Name_Until
then
1387 Check_95_Keyword
(Tok_Until
, Tok_Left_Paren
);
1388 Check_95_Keyword
(Tok_Until
, Tok_Identifier
);
1391 if Token
= Tok_Until
then
1392 return P_Delay_Until_Statement
;
1394 return P_Delay_Relative_Statement
;
1396 end P_Delay_Statement
;
1398 --------------------------------
1399 -- 9.6 Delay Until Statement --
1400 --------------------------------
1402 -- DELAY_UNTIL_STATEMENT ::= delay until delay_EXPRESSION;
1404 -- The caller has checked that the initial token is DELAY, scanned it
1405 -- out and checked that the current token is UNTIL
1407 -- Error recovery: cannot raise Error_Resync
1409 function P_Delay_Until_Statement
return Node_Id
is
1410 Delay_Node
: Node_Id
;
1413 Delay_Node
:= New_Node
(N_Delay_Until_Statement
, Prev_Token_Ptr
);
1415 Set_Expression
(Delay_Node
, P_Expression_No_Right_Paren
);
1418 end P_Delay_Until_Statement
;
1420 -----------------------------------
1421 -- 9.6 Delay Relative Statement --
1422 -----------------------------------
1424 -- DELAY_RELATIVE_STATEMENT ::= delay delay_EXPRESSION;
1426 -- The caller has checked that the initial token is DELAY, scanned it
1427 -- out and determined that the current token is not UNTIL
1429 -- Error recovery: cannot raise Error_Resync
1431 function P_Delay_Relative_Statement
return Node_Id
is
1432 Delay_Node
: Node_Id
;
1435 Delay_Node
:= New_Node
(N_Delay_Relative_Statement
, Prev_Token_Ptr
);
1436 Set_Expression
(Delay_Node
, P_Expression_No_Right_Paren
);
1437 Check_Simple_Expression_In_Ada_83
(Expression
(Delay_Node
));
1440 end P_Delay_Relative_Statement
;
1442 ---------------------------
1443 -- 9.7 Select Statement --
1444 ---------------------------
1446 -- SELECT_STATEMENT ::=
1448 -- | TIMED_ENTRY_CALL
1449 -- | CONDITIONAL_ENTRY_CALL
1450 -- | ASYNCHRONOUS_SELECT
1452 -- SELECTIVE_ACCEPT ::=
1455 -- SELECT_ALTERNATIVE
1458 -- SELECT_ALTERNATIVE
1460 -- SEQUENCE_OF_STATEMENTS]
1463 -- GUARD ::= when CONDITION =>
1465 -- Note: the guard preceding a select alternative is included as part
1466 -- of the node generated for a selective accept alternative.
1468 -- SELECT_ALTERNATIVE ::=
1469 -- ACCEPT_ALTERNATIVE
1470 -- | DELAY_ALTERNATIVE
1471 -- | TERMINATE_ALTERNATIVE
1473 -- TIMED_ENTRY_CALL ::=
1475 -- ENTRY_CALL_ALTERNATIVE
1477 -- DELAY_ALTERNATIVE
1480 -- CONDITIONAL_ENTRY_CALL ::=
1482 -- ENTRY_CALL_ALTERNATIVE
1484 -- SEQUENCE_OF_STATEMENTS
1487 -- ENTRY_CALL_ALTERNATIVE ::=
1488 -- ENTRY_CALL_STATEMENT [SEQUENCE_OF_STATEMENTS]
1490 -- ASYNCHRONOUS_SELECT ::=
1492 -- TRIGGERING_ALTERNATIVE
1497 -- TRIGGERING_ALTERNATIVE ::=
1498 -- TRIGGERING_STATEMENT [SEQUENCE_OF_STATEMENTS]
1500 -- TRIGGERING_STATEMENT ::= ENTRY_CALL_STATEMENT | DELAY_STATEMENT
1502 -- The caller has checked that the initial token is SELECT
1504 -- Error recovery: can raise Error_Resync
1506 function P_Select_Statement
return Node_Id
is
1507 Select_Node
: Node_Id
;
1508 Select_Sloc
: Source_Ptr
;
1509 Stmnt_Sloc
: Source_Ptr
;
1510 Ecall_Node
: Node_Id
;
1511 Alternative
: Node_Id
;
1512 Select_Pragmas
: List_Id
;
1513 Alt_Pragmas
: List_Id
;
1514 Statement_List
: List_Id
;
1516 Cond_Expr
: Node_Id
;
1517 Delay_Stmnt
: Node_Id
;
1521 Scopes
(Scope
.Last
).Etyp
:= E_Select
;
1522 Scopes
(Scope
.Last
).Ecol
:= Start_Column
;
1523 Scopes
(Scope
.Last
).Sloc
:= Token_Ptr
;
1524 Scopes
(Scope
.Last
).Labl
:= Error
;
1526 Select_Sloc
:= Token_Ptr
;
1527 Scan
; -- past SELECT
1528 Stmnt_Sloc
:= Token_Ptr
;
1529 Select_Pragmas
:= P_Pragmas_Opt
;
1531 -- If first token after select is designator, then we have an entry
1532 -- call, which must be the start of a conditional entry call, timed
1533 -- entry call or asynchronous select
1535 if Token
in Token_Class_Desig
then
1537 -- Scan entry call statement
1540 Ecall_Node
:= P_Name
;
1542 -- ?? The following two clauses exactly parallel code in ch5
1543 -- and should be combined sometime
1545 if Nkind
(Ecall_Node
) = N_Indexed_Component
then
1547 Prefix_Node
: constant Node_Id
:= Prefix
(Ecall_Node
);
1548 Exprs_Node
: constant List_Id
:= Expressions
(Ecall_Node
);
1551 Change_Node
(Ecall_Node
, N_Procedure_Call_Statement
);
1552 Set_Name
(Ecall_Node
, Prefix_Node
);
1553 Set_Parameter_Associations
(Ecall_Node
, Exprs_Node
);
1556 elsif Nkind
(Ecall_Node
) = N_Function_Call
then
1558 Fname_Node
: constant Node_Id
:= Name
(Ecall_Node
);
1559 Params_List
: constant List_Id
:=
1560 Parameter_Associations
(Ecall_Node
);
1563 Change_Node
(Ecall_Node
, N_Procedure_Call_Statement
);
1564 Set_Name
(Ecall_Node
, Fname_Node
);
1565 Set_Parameter_Associations
(Ecall_Node
, Params_List
);
1568 elsif Nkind
(Ecall_Node
) = N_Identifier
1569 or else Nkind
(Ecall_Node
) = N_Selected_Component
1571 -- Case of a call to a parameterless entry
1574 C_Node
: constant Node_Id
:=
1575 New_Node
(N_Procedure_Call_Statement
, Stmnt_Sloc
);
1577 Set_Name
(C_Node
, Ecall_Node
);
1578 Set_Parameter_Associations
(C_Node
, No_List
);
1579 Ecall_Node
:= C_Node
;
1586 when Error_Resync
=>
1587 Resync_Past_Semicolon
;
1591 Statement_List
:= P_Sequence_Of_Statements
(SS_Eltm_Ortm_Tatm
);
1593 -- OR follows, we have a timed entry call
1595 if Token
= Tok_Or
then
1597 Alt_Pragmas
:= P_Pragmas_Opt
;
1599 Select_Node
:= New_Node
(N_Timed_Entry_Call
, Select_Sloc
);
1600 Set_Entry_Call_Alternative
(Select_Node
,
1601 Make_Entry_Call_Alternative
(Stmnt_Sloc
,
1602 Entry_Call_Statement
=> Ecall_Node
,
1603 Pragmas_Before
=> Select_Pragmas
,
1604 Statements
=> Statement_List
));
1606 -- Only possibility is delay alternative. If we have anything
1607 -- else, give message, and treat as conditional entry call.
1609 if Token
/= Tok_Delay
then
1611 ("only allowed alternative in timed entry call is delay!");
1612 Discard_Junk_List
(P_Sequence_Of_Statements
(SS_Sreq
));
1613 Set_Delay_Alternative
(Select_Node
, Error
);
1616 Set_Delay_Alternative
(Select_Node
, P_Delay_Alternative
);
1618 (Delay_Alternative
(Select_Node
), Alt_Pragmas
);
1621 -- ELSE follows, we have a conditional entry call
1623 elsif Token
= Tok_Else
then
1625 Select_Node
:= New_Node
(N_Conditional_Entry_Call
, Select_Sloc
);
1627 Set_Entry_Call_Alternative
(Select_Node
,
1628 Make_Entry_Call_Alternative
(Stmnt_Sloc
,
1629 Entry_Call_Statement
=> Ecall_Node
,
1630 Pragmas_Before
=> Select_Pragmas
,
1631 Statements
=> Statement_List
));
1634 (Select_Node
, P_Sequence_Of_Statements
(SS_Sreq
));
1636 -- Only remaining case is THEN ABORT (asynchronous select)
1638 elsif Token
= Tok_Abort
then
1640 Make_Asynchronous_Select
(Select_Sloc
,
1641 Triggering_Alternative
=>
1642 Make_Triggering_Alternative
(Stmnt_Sloc
,
1643 Triggering_Statement
=> Ecall_Node
,
1644 Pragmas_Before
=> Select_Pragmas
,
1645 Statements
=> Statement_List
),
1646 Abortable_Part
=> P_Abortable_Part
);
1651 if Ada_Version
= Ada_83
then
1652 Error_Msg_BC
("OR or ELSE expected");
1654 Error_Msg_BC
("OR or ELSE or `THEN ABORT` expected");
1657 Select_Node
:= Error
;
1662 -- Here we have a selective accept or an asynchronous select (first
1663 -- token after SELECT is other than a designator token).
1666 -- If we have delay with no guard, could be asynchronous select
1668 if Token
= Tok_Delay
then
1669 Delay_Stmnt
:= P_Delay_Statement
;
1670 Statement_List
:= P_Sequence_Of_Statements
(SS_Eltm_Ortm_Tatm
);
1672 -- Asynchronous select
1674 if Token
= Tok_Abort
then
1676 Make_Asynchronous_Select
(Select_Sloc
,
1677 Triggering_Alternative
=>
1678 Make_Triggering_Alternative
(Stmnt_Sloc
,
1679 Triggering_Statement
=> Delay_Stmnt
,
1680 Pragmas_Before
=> Select_Pragmas
,
1681 Statements
=> Statement_List
),
1682 Abortable_Part
=> P_Abortable_Part
);
1687 -- Delay which was not an asynchronous select. Must be a selective
1688 -- accept, and since at least one accept statement is required,
1689 -- we must have at least one OR phrase present.
1692 Alt_List
:= New_List
(
1693 Make_Delay_Alternative
(Stmnt_Sloc
,
1694 Delay_Statement
=> Delay_Stmnt
,
1695 Pragmas_Before
=> Select_Pragmas
,
1696 Statements
=> Statement_List
));
1698 Alt_Pragmas
:= P_Pragmas_Opt
;
1701 -- If not a delay statement, then must be another possibility for
1702 -- a selective accept alternative, or perhaps a guard is present
1705 Alt_List
:= New_List
;
1706 Alt_Pragmas
:= Select_Pragmas
;
1709 Select_Node
:= New_Node
(N_Selective_Accept
, Select_Sloc
);
1710 Set_Select_Alternatives
(Select_Node
, Alt_List
);
1712 -- Scan out selective accept alternatives. On entry to this loop,
1713 -- we are just past a SELECT or OR token, and any pragmas that
1714 -- immediately follow the SELECT or OR are in Alt_Pragmas.
1717 if Token
= Tok_When
then
1719 if Present
(Alt_Pragmas
) then
1720 Error_Msg_SC
("pragmas may not precede guard");
1724 Cond_Expr
:= P_Expression_No_Right_Paren
;
1726 Alt_Pragmas
:= P_Pragmas_Opt
;
1732 if Token
= Tok_Accept
then
1733 Alternative
:= P_Accept_Alternative
;
1735 -- Check for junk attempt at asynchronous select using
1736 -- an Accept alternative as the triggering statement
1738 if Token
= Tok_Abort
1739 and then Is_Empty_List
(Alt_List
)
1740 and then No
(Cond_Expr
)
1743 ("triggering statement must be entry call or delay",
1744 Sloc
(Alternative
));
1745 Scan
; -- past junk ABORT
1746 Discard_Junk_List
(P_Sequence_Of_Statements
(SS_Sreq
));
1751 elsif Token
= Tok_Delay
then
1752 Alternative
:= P_Delay_Alternative
;
1754 elsif Token
= Tok_Terminate
then
1755 Alternative
:= P_Terminate_Alternative
;
1759 ("select alternative (ACCEPT, ABORT, DELAY) expected");
1760 Alternative
:= Error
;
1762 if Token
= Tok_Semicolon
then
1763 Scan
; -- past junk semicolon
1767 -- THEN ABORT at this stage is just junk
1769 if Token
= Tok_Abort
then
1770 Error_Msg_SP
("misplaced `THEN ABORT`");
1771 Scan
; -- past junk ABORT
1772 Discard_Junk_List
(P_Sequence_Of_Statements
(SS_Sreq
));
1777 if Alternative
/= Error
then
1778 Set_Condition
(Alternative
, Cond_Expr
);
1779 Set_Pragmas_Before
(Alternative
, Alt_Pragmas
);
1780 Append
(Alternative
, Alt_List
);
1783 exit when Token
/= Tok_Or
;
1787 Alt_Pragmas
:= P_Pragmas_Opt
;
1790 if Token
= Tok_Else
then
1793 (Select_Node
, P_Sequence_Of_Statements
(SS_Ortm_Sreq
));
1795 if Token
= Tok_Or
then
1796 Error_Msg_SC
("select alternative cannot follow else part!");
1804 end P_Select_Statement
;
1806 -----------------------------
1807 -- 9.7.1 Selective Accept --
1808 -----------------------------
1810 -- Parsed by P_Select_Statement (9.7)
1816 -- Parsed by P_Select_Statement (9.7)
1818 -------------------------------
1819 -- 9.7.1 Select Alternative --
1820 -------------------------------
1822 -- SELECT_ALTERNATIVE ::=
1823 -- ACCEPT_ALTERNATIVE
1824 -- | DELAY_ALTERNATIVE
1825 -- | TERMINATE_ALTERNATIVE
1827 -- Note: the guard preceding a select alternative is included as part
1828 -- of the node generated for a selective accept alternative.
1830 -- Error recovery: cannot raise Error_Resync
1832 -------------------------------
1833 -- 9.7.1 Accept Alternative --
1834 -------------------------------
1836 -- ACCEPT_ALTERNATIVE ::=
1837 -- ACCEPT_STATEMENT [SEQUENCE_OF_STATEMENTS]
1839 -- Error_Recovery: Cannot raise Error_Resync
1841 -- Note: the caller is responsible for setting the Pragmas_Before
1842 -- field of the returned N_Terminate_Alternative node.
1844 function P_Accept_Alternative
return Node_Id
is
1845 Accept_Alt_Node
: Node_Id
;
1848 Accept_Alt_Node
:= New_Node
(N_Accept_Alternative
, Token_Ptr
);
1849 Set_Accept_Statement
(Accept_Alt_Node
, P_Accept_Statement
);
1851 -- Note: the reason that we accept THEN ABORT as a terminator for
1852 -- the sequence of statements is for error recovery which allows
1853 -- for misuse of an accept statement as a triggering statement.
1856 (Accept_Alt_Node
, P_Sequence_Of_Statements
(SS_Eltm_Ortm_Tatm
));
1857 return Accept_Alt_Node
;
1858 end P_Accept_Alternative
;
1860 ------------------------------
1861 -- 9.7.1 Delay Alternative --
1862 ------------------------------
1864 -- DELAY_ALTERNATIVE ::=
1865 -- DELAY_STATEMENT [SEQUENCE_OF_STATEMENTS]
1867 -- Error_Recovery: Cannot raise Error_Resync
1869 -- Note: the caller is responsible for setting the Pragmas_Before
1870 -- field of the returned N_Terminate_Alternative node.
1872 function P_Delay_Alternative
return Node_Id
is
1873 Delay_Alt_Node
: Node_Id
;
1876 Delay_Alt_Node
:= New_Node
(N_Delay_Alternative
, Token_Ptr
);
1877 Set_Delay_Statement
(Delay_Alt_Node
, P_Delay_Statement
);
1879 -- Note: the reason that we accept THEN ABORT as a terminator for
1880 -- the sequence of statements is for error recovery which allows
1881 -- for misuse of an accept statement as a triggering statement.
1884 (Delay_Alt_Node
, P_Sequence_Of_Statements
(SS_Eltm_Ortm_Tatm
));
1885 return Delay_Alt_Node
;
1886 end P_Delay_Alternative
;
1888 ----------------------------------
1889 -- 9.7.1 Terminate Alternative --
1890 ----------------------------------
1892 -- TERMINATE_ALTERNATIVE ::= terminate;
1894 -- Error_Recovery: Cannot raise Error_Resync
1896 -- Note: the caller is responsible for setting the Pragmas_Before
1897 -- field of the returned N_Terminate_Alternative node.
1899 function P_Terminate_Alternative
return Node_Id
is
1900 Terminate_Alt_Node
: Node_Id
;
1903 Terminate_Alt_Node
:= New_Node
(N_Terminate_Alternative
, Token_Ptr
);
1904 Scan
; -- past TERMINATE
1907 -- For all other select alternatives, the sequence of statements
1908 -- after the alternative statement will swallow up any pragmas
1909 -- coming in this position. But the terminate alternative has no
1910 -- sequence of statements, so the pragmas here must be treated
1913 Set_Pragmas_After
(Terminate_Alt_Node
, P_Pragmas_Opt
);
1914 return Terminate_Alt_Node
;
1915 end P_Terminate_Alternative
;
1917 -----------------------------
1918 -- 9.7.2 Timed Entry Call --
1919 -----------------------------
1921 -- Parsed by P_Select_Statement (9.7)
1923 -----------------------------------
1924 -- 9.7.2 Entry Call Alternative --
1925 -----------------------------------
1927 -- Parsed by P_Select_Statement (9.7)
1929 -----------------------------------
1930 -- 9.7.3 Conditional Entry Call --
1931 -----------------------------------
1933 -- Parsed by P_Select_Statement (9.7)
1935 --------------------------------
1936 -- 9.7.4 Asynchronous Select --
1937 --------------------------------
1939 -- Parsed by P_Select_Statement (9.7)
1941 -----------------------------------
1942 -- 9.7.4 Triggering Alternative --
1943 -----------------------------------
1945 -- Parsed by P_Select_Statement (9.7)
1947 ---------------------------------
1948 -- 9.7.4 Triggering Statement --
1949 ---------------------------------
1951 -- Parsed by P_Select_Statement (9.7)
1953 ---------------------------
1954 -- 9.7.4 Abortable Part --
1955 ---------------------------
1957 -- ABORTABLE_PART ::= SEQUENCE_OF_STATEMENTS
1959 -- The caller has verified that THEN ABORT is present, and Token is
1960 -- pointing to the ABORT on entry (or if not, then we have an error)
1962 -- Error recovery: cannot raise Error_Resync
1964 function P_Abortable_Part
return Node_Id
is
1965 Abortable_Part_Node
: Node_Id
;
1968 Abortable_Part_Node
:= New_Node
(N_Abortable_Part
, Token_Ptr
);
1969 T_Abort
; -- scan past ABORT
1971 if Ada_Version
= Ada_83
then
1972 Error_Msg_SP
("(Ada 83) asynchronous select not allowed!");
1975 Set_Statements
(Abortable_Part_Node
, P_Sequence_Of_Statements
(SS_Sreq
));
1976 return Abortable_Part_Node
;
1977 end P_Abortable_Part
;
1979 --------------------------
1980 -- 9.8 Abort Statement --
1981 --------------------------
1983 -- ABORT_STATEMENT ::= abort task_NAME {, task_NAME};
1985 -- The caller has checked that the initial token is ABORT
1987 -- Error recovery: cannot raise Error_Resync
1989 function P_Abort_Statement
return Node_Id
is
1990 Abort_Node
: Node_Id
;
1993 Abort_Node
:= New_Node
(N_Abort_Statement
, Token_Ptr
);
1995 Set_Names
(Abort_Node
, New_List
);
1998 Append
(P_Name
, Names
(Abort_Node
));
1999 exit when Token
/= Tok_Comma
;
2005 end P_Abort_Statement
;