1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2005 Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 2, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING. If not, write --
19 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
20 -- MA 02111-1307, USA. --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
25 ------------------------------------------------------------------------------
27 pragma Style_Checks
(All_Checks
);
28 -- Turn off subprogram body ordering check. Subprograms are in order
29 -- by RM section rather than alphabetical
34 -- Local functions, used only in this chapter
36 function P_Pragma_Argument_Association
return Node_Id
;
42 -- IDENTIFIER ::= LETTER {[UNDERLINE] LETTER_OR_DIGIT}
44 -- LETTER_OR_DIGIT ::= IDENTIFIER_LETTER | DIGIT
46 -- An IDENTIFIER shall not be a reserved word
48 -- Error recovery: can raise Error_Resync (cannot return Error)
50 function P_Identifier
(C
: Id_Check
:= None
) return Node_Id
is
54 -- All set if we do indeed have an identifier
56 if Token
= Tok_Identifier
then
58 -- Ada 2005 (AI-284): Compiling in Ada95 mode we notify
59 -- that interface, overriding, and synchronized are
62 if Ada_Version
= Ada_95
then
63 if Token_Name
= Name_Overriding
64 or else Token_Name
= Name_Synchronized
65 or else (Token_Name
= Name_Interface
66 and then Prev_Token
/= Tok_Pragma
)
68 Error_Msg_N
("& is a reserved word in Ada 2005?", Token_Node
);
72 Ident_Node
:= Token_Node
;
73 Scan
; -- past Identifier
76 -- If we have a reserved identifier, manufacture an identifier with
77 -- a corresponding name after posting an appropriate error message
79 elsif Is_Reserved_Identifier
(C
) then
80 Scan_Reserved_Identifier
(Force_Msg
=> False);
81 Ident_Node
:= Token_Node
;
82 Scan
; -- past the node
85 -- Otherwise we have junk that cannot be interpreted as an identifier
88 T_Identifier
; -- to give message
93 --------------------------
94 -- 2.3 Letter Or Digit --
95 --------------------------
97 -- Parsed by P_Identifier (2.3)
99 --------------------------
100 -- 2.4 Numeric Literal --
101 --------------------------
103 -- NUMERIC_LITERAL ::= DECIMAL_LITERAL | BASED_LITERAL
105 -- Numeric literal is returned by the scanner as either
106 -- Tok_Integer_Literal or Tok_Real_Literal
108 ----------------------------
109 -- 2.4.1 Decimal Literal --
110 ----------------------------
112 -- DECIMAL_LITERAL ::= NUMERAL [.NUMERAL] [EXPONENT]
114 -- Handled by scanner as part of numeric lIteral handing (see 2.4)
120 -- NUMERAL ::= DIGIT {[UNDERLINE] DIGIT}
122 -- Handled by scanner as part of numeric literal handling (see 2.4)
124 ---------------------
126 ---------------------
128 -- EXPONENT ::= E [+] NUMERAL | E - NUMERAL
130 -- Handled by scanner as part of numeric literal handling (see 2.4)
132 --------------------------
133 -- 2.4.2 Based Literal --
134 --------------------------
137 -- BASE # BASED_NUMERAL [.BASED_NUMERAL] # [EXPONENT]
139 -- Handled by scanner as part of numeric literal handling (see 2.4)
147 -- Handled by scanner as part of numeric literal handling (see 2.4)
149 --------------------------
150 -- 2.4.2 Based Numeral --
151 --------------------------
154 -- EXTENDED_DIGIT {[UNDERLINE] EXTENDED_DIGIT}
156 -- Handled by scanner as part of numeric literal handling (see 2.4)
158 ---------------------------
159 -- 2.4.2 Extended Digit --
160 ---------------------------
162 -- EXTENDED_DIGIT ::= DIGIT | A | B | C | D | E | F
164 -- Handled by scanner as part of numeric literal handling (see 2.4)
166 ----------------------------
167 -- 2.5 Character Literal --
168 ----------------------------
170 -- CHARACTER_LITERAL ::= ' GRAPHIC_CHARACTER '
172 -- Handled by the scanner and returned as Tok_Character_Literal
174 -------------------------
175 -- 2.6 String Literal --
176 -------------------------
178 -- STRING LITERAL ::= "{STRING_ELEMENT}"
180 -- Handled by the scanner and returned as Tok_Character_Literal
181 -- or if the string looks like an operator as Tok_Operator_Symbol.
183 -------------------------
184 -- 2.6 String Element --
185 -------------------------
187 -- STRING_ELEMENT ::= "" | non-quotation_mark_GRAPHIC_CHARACTER
189 -- A STRING_ELEMENT is either a pair of quotation marks ("),
190 -- or a single GRAPHIC_CHARACTER other than a quotation mark.
192 -- Handled by scanner as part of string literal handling (see 2.4)
198 -- A COMMENT starts with two adjacent hyphens and extends up to the
199 -- end of the line. A COMMENT may appear on any line of a program.
201 -- Handled by the scanner which simply skips past encountered comments
207 -- PRAGMA ::= pragma IDENTIFIER
208 -- [(PRAGMA_ARGUMENT_ASSOCIATION {, PRAGMA_ARGUMENT_ASSOCIATION})];
210 -- The caller has checked that the initial token is PRAGMA
212 -- Error recovery: cannot raise Error_Resync
214 -- One special piece of processing is needed in this routine. As described
215 -- in the section on "Handling semicolon used in place of IS" in module
216 -- Parse, the parser detects the case of missing subprogram bodies to
217 -- allow recovery from this syntactic error. Pragma INTERFACE (and, for
218 -- Ada 95, pragma IMPORT) can appear in place of the body. The parser must
219 -- recognize the use of these two pragmas in this context, otherwise it
220 -- will think there are missing bodies, and try to change ; to IS, when
221 -- in fact the bodies ARE present, supplied by these pragmas.
223 function P_Pragma
return Node_Id
is
225 Interface_Check_Required
: Boolean := False;
226 -- Set True if check of pragma INTERFACE is required
228 Import_Check_Required
: Boolean := False;
229 -- Set True if check of pragma IMPORT is required
231 Arg_Count
: Int
:= 0;
232 -- Number of argument associations processed
234 Pragma_Node
: Node_Id
;
235 Pragma_Name
: Name_Id
;
236 Semicolon_Loc
: Source_Ptr
;
237 Ident_Node
: Node_Id
;
238 Assoc_Node
: Node_Id
;
241 procedure Skip_Pragma_Semicolon
;
242 -- Skip past semicolon at end of pragma
244 ---------------------------
245 -- Skip_Pragma_Semicolon --
246 ---------------------------
248 procedure Skip_Pragma_Semicolon
is
250 if Token
/= Tok_Semicolon
then
252 Resync_Past_Semicolon
;
254 Scan
; -- past semicolon
256 end Skip_Pragma_Semicolon
;
258 -- Start of processing for P_Pragma
261 Pragma_Node
:= New_Node
(N_Pragma
, Token_Ptr
);
263 Pragma_Name
:= Token_Name
;
266 Style
.Check_Pragma_Name
;
269 -- Ada 2005 (AI-284): INTERFACE is a new reserved word but it is
270 -- allowed as a pragma name.
272 if Ada_Version
>= Ada_05
273 and then Token
= Tok_Interface
275 Pragma_Name
:= Name_Interface
;
276 Ident_Node
:= Token_Node
;
277 Scan
; -- past INTERFACE
279 Ident_Node
:= P_Identifier
;
280 Delete_Node
(Ident_Node
);
283 Set_Chars
(Pragma_Node
, Pragma_Name
);
285 -- See if special INTERFACE/IMPORT check is required
287 if SIS_Entry_Active
then
288 Interface_Check_Required
:= (Pragma_Name
= Name_Interface
);
289 Import_Check_Required
:= (Pragma_Name
= Name_Import
);
291 Interface_Check_Required
:= False;
292 Import_Check_Required
:= False;
295 -- Scan arguments. We assume that arguments are present if there is
296 -- a left paren, or if a semicolon is missing and there is another
297 -- token on the same line as the pragma name.
299 if Token
= Tok_Left_Paren
300 or else (Token
/= Tok_Semicolon
301 and then not Token_Is_At_Start_Of_Line
)
303 Set_Pragma_Argument_Associations
(Pragma_Node
, New_List
);
307 Arg_Count
:= Arg_Count
+ 1;
308 Assoc_Node
:= P_Pragma_Argument_Association
;
311 and then (Interface_Check_Required
or else Import_Check_Required
)
313 -- Here is where we cancel the SIS active status if this pragma
314 -- supplies a body for the currently active subprogram spec.
316 if Nkind
(Expression
(Assoc_Node
)) in N_Direct_Name
317 and then Chars
(Expression
(Assoc_Node
)) = Chars
(SIS_Labl
)
319 SIS_Entry_Active
:= False;
323 Append
(Assoc_Node
, Pragma_Argument_Associations
(Pragma_Node
));
324 exit when Token
/= Tok_Comma
;
328 -- If we have := for pragma Debug, it is worth special casing
329 -- the error message (it is easy to think of pragma Debug as
330 -- taking a statement, and an assignment statement is the most
331 -- likely candidate for this error)
333 if Token
= Tok_Colon_Equal
and then Pragma_Name
= Name_Debug
then
334 Error_Msg_SC
("argument for pragma Debug must be procedure call");
337 -- Normal case, we expect a right paren here
344 Semicolon_Loc
:= Token_Ptr
;
346 -- Now we have two tasks left, we need to scan out the semicolon
347 -- following the pragma, and we have to call Par.Prag to process
348 -- the pragma. Normally we do them in this order, however, there
349 -- is one exception namely pragma Style_Checks where we like to
350 -- skip the semicolon after processing the pragma, since that way
351 -- the style checks for the scanning of the semicolon follow the
352 -- settings of the pragma.
354 -- You might think we could just unconditionally do things in
355 -- the opposite order, but there are other pragmas, notably the
356 -- case of pragma Source_File_Name, which assume the semicolon
357 -- is already scanned out.
359 if Chars
(Pragma_Node
) = Name_Style_Checks
then
360 Result
:= Par
.Prag
(Pragma_Node
, Semicolon_Loc
);
361 Skip_Pragma_Semicolon
;
364 Skip_Pragma_Semicolon
;
365 return Par
.Prag
(Pragma_Node
, Semicolon_Loc
);
370 Resync_Past_Semicolon
;
375 -- This routine is called if a pragma is encountered in an inappropriate
376 -- position, the pragma is scanned out and control returns to continue.
378 -- The caller has checked that the initial token is pragma
380 -- Error recovery: cannot raise Error_Resync
382 procedure P_Pragmas_Misplaced
is
384 while Token
= Tok_Pragma
loop
385 Error_Msg_SC
("pragma not allowed here");
386 Discard_Junk_Node
(P_Pragma
);
388 end P_Pragmas_Misplaced
;
390 -- This function is called to scan out an optional sequence of pragmas.
391 -- If no pragmas are found, then No_List is returned.
393 -- Error recovery: Cannot raise Error_Resync
395 function P_Pragmas_Opt
return List_Id
is
399 if Token
= Tok_Pragma
then
409 -- This procedure is called to scan out an optional sequence of pragmas.
410 -- Any pragmas found are appended to the list provided as an argument.
412 -- Error recovery: Cannot raise Error_Resync
414 procedure P_Pragmas_Opt
(List
: List_Id
) is
418 while Token
= Tok_Pragma
loop
421 if Chars
(P
) = Name_Assert
or else Chars
(P
) = Name_Debug
then
422 Error_Msg_Name_1
:= Chars
(P
);
424 ("pragma% must be in declaration/statement context", P
);
431 --------------------------------------
432 -- 2.8 Pragma_Argument Association --
433 --------------------------------------
435 -- PRAGMA_ARGUMENT_ASSOCIATION ::=
436 -- [pragma_argument_IDENTIFIER =>] NAME
437 -- | [pragma_argument_IDENTIFIER =>] EXPRESSION
439 -- Error recovery: cannot raise Error_Resync
441 function P_Pragma_Argument_Association
return Node_Id
is
442 Scan_State
: Saved_Scan_State
;
443 Pragma_Arg_Node
: Node_Id
;
444 Identifier_Node
: Node_Id
;
447 Pragma_Arg_Node
:= New_Node
(N_Pragma_Argument_Association
, Token_Ptr
);
448 Set_Chars
(Pragma_Arg_Node
, No_Name
);
450 if Token
= Tok_Identifier
then
451 Identifier_Node
:= Token_Node
;
452 Save_Scan_State
(Scan_State
); -- at Identifier
453 Scan
; -- past Identifier
455 if Token
= Tok_Arrow
then
457 Set_Chars
(Pragma_Arg_Node
, Chars
(Identifier_Node
));
458 Delete_Node
(Identifier_Node
);
460 Restore_Scan_State
(Scan_State
); -- to Identifier
464 Set_Expression
(Pragma_Arg_Node
, P_Expression
);
465 return Pragma_Arg_Node
;
467 end P_Pragma_Argument_Association
;