X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/f6857bbf8c40df05d7c7324cf41ced6d1961ca89..4f646c3794c45940aaf96d5409eff02a2c74978e:/src/scan-code.l
diff --git a/src/scan-code.l b/src/scan-code.l
index b54f4c9a..88f89902 100644
--- a/src/scan-code.l
+++ b/src/scan-code.l
@@ -1,12 +1,12 @@
/* Bison Action Scanner -*- C -*-
- Copyright (C) 2006, 2007 Free Software Foundation, Inc.
+ Copyright (C) 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
This file is part of Bison, the GNU Compiler Compiler.
- This program is free software; you can redistribute it and/or modify
+ This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
+ the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
@@ -15,10 +15,7 @@
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
- 02110-1301 USA
-*/
+ along with this program. If not, see . */
%option debug nodefault nounput noyywrap never-interactive
%option prefix="code_" outfile="lex.yy.c"
@@ -30,16 +27,16 @@
#define code_wrap() 1
#define FLEX_PREFIX(Id) code_ ## Id
-#include "flex-scanner.h"
+#include
-#include "complain.h"
-#include "reader.h"
-#include "getargs.h"
+#include
+#include
+#include
#include
#include
-
-#include "scan-code.h"
-#include "symlist.h"
+#include
+#include
+#include
/* The current calling start condition: SC_RULE_ACTION or
SC_SYMBOL_ACTION. */
@@ -84,6 +81,19 @@ splice (\\[ \f\t\v]*\n)*
/* Nesting level of the current code in braces. */
int braces_level = 0;
+ /* Whether a semicolon is probably needed.
+ The heuristic is that a semicolon is not needed after `{', `}', `;',
+ or a C preprocessor directive, and that whitespaces and comments
+ do not affect this flag.
+ Note that `{' does not need a semicolon because of `{}'.
+ A semicolon may be needed before a cpp direcive, but don't bother. */
+ bool need_semicolon = false;
+
+ /* Whether in a C preprocessor directive. Don't use a start condition
+ for this because, at the end of strings and comments, we still need
+ to know whether we're in a directive. */
+ bool in_cpp = false;
+
/* This scanner is special: it is invoked only once, henceforth
is expected to return only once. This initialization is
therefore done once per action to translate. */
@@ -138,10 +148,12 @@ splice (\\[ \f\t\v]*\n)*
"'" {
STRING_GROW;
BEGIN SC_CHARACTER;
+ need_semicolon = true;
}
"\"" {
STRING_GROW;
BEGIN SC_STRING;
+ need_semicolon = true;
}
"/"{splice}"*" {
STRING_GROW;
@@ -157,43 +169,63 @@ splice (\\[ \f\t\v]*\n)*
{
"$"("<"{tag}">")?(-?[0-9]+|"$") {
handle_action_dollar (self->rule, yytext, *loc);
+ need_semicolon = true;
}
"@"(-?[0-9]+|"$") {
handle_action_at (self->rule, yytext, *loc);
+ need_semicolon = true;
}
"$" {
warn_at (*loc, _("stray `$'"));
obstack_sgrow (&obstack_for_string, "$][");
+ need_semicolon = true;
}
"@" {
warn_at (*loc, _("stray `@'"));
obstack_sgrow (&obstack_for_string, "@@");
+ need_semicolon = true;
+ }
+ "[" {
+ obstack_sgrow (&obstack_for_string, "@{");
+ need_semicolon = true;
+ }
+ "]" {
+ obstack_sgrow (&obstack_for_string, "@}");
+ need_semicolon = true;
}
- "{" STRING_GROW; ++braces_level;
+ ";" STRING_GROW; need_semicolon = false;
+ "{" STRING_GROW; ++braces_level; need_semicolon = false;
"}" {
- bool outer_brace = --braces_level < 0;
+ bool outer_brace = --braces_level == 0;
/* As an undocumented Bison extension, append `;' before the last
brace in braced code, so that the user code can omit trailing
`;'. But do not append `;' if emulating Yacc, since Yacc does
- not append one.
-
- FIXME: Bison should warn if a semicolon seems to be necessary
- here, and should omit the semicolon if it seems unnecessary
- (e.g., after ';', '{', or '}', each followed by comments or
- white space). Such a warning shouldn't depend on --yacc; it
- should depend on a new --pedantic option, which would cause
- Bison to warn if it detects an extension to POSIX. --pedantic
- should also diagnose other Bison extensions like %yacc.
- Perhaps there should also be a GCC-style --pedantic-errors
- option, so that such warnings are diagnosed as errors. */
- if (outer_brace && ! yacc_flag)
- obstack_1grow (&obstack_for_string, ';');
+ not append one. */
+ if (outer_brace && !yacc_flag && language_prio == default_prio
+ && skeleton_prio == default_prio && need_semicolon && ! in_cpp)
+ {
+ warn_at (*loc, _("a `;' might be needed at the end of action code"));
+ warn_at (*loc, _("future versions of Bison will not add the `;'"));
+ obstack_1grow (&obstack_for_string, ';');
+ }
STRING_GROW;
+ need_semicolon = false;
}
+
+ /* Preprocessing directives should only be recognized at the beginning
+ of lines, allowing whitespace including comments, but in C/C++,
+ `#' can only be the start of preprocessor directives or within
+ `#define' directives anyway, so don't bother with begin of line. */
+ "#" STRING_GROW; in_cpp = true;
+
+ {splice} STRING_GROW;
+ [\n\r] STRING_GROW; if (in_cpp) in_cpp = need_semicolon = false;
+ [ \t\f] STRING_GROW;
+ . STRING_GROW; need_semicolon = true;
}
@@ -202,7 +234,10 @@ splice (\\[ \f\t\v]*\n)*
obstack_sgrow (&obstack_for_string, "]b4_dollar_dollar[");
self->is_value_used = true;
}
- "@$" obstack_sgrow (&obstack_for_string, "]b4_at_dollar[");
+ "@$" {
+ obstack_sgrow (&obstack_for_string, "]b4_at_dollar[");
+ muscle_percent_define_ensure("locations", the_location, true);
+ }
}
@@ -356,7 +391,7 @@ handle_action_at (symbol_list *rule, char *text, location at_loc)
? rule->midrule_parent_rhs_index - 1
: symbol_list_length (rule->next));
- locations_flag = true;
+ muscle_percent_define_ensure("locations", at_loc, true);
if (*cp == '$')
obstack_sgrow (&obstack_for_string, "]b4_lhs_location[");