Re: Scanner robustness

[Akim Demaille]

>>>>> "Akim" == Akim Demaille <address@hidden> writes:

Akim> I have also discovered $-n is not supported properly.  To be
Akim> checked + fixed.

I forgot to send the patch :)

Index: ChangeLog
from  Akim Demaille  <address@hidden>

        * src/scan-gram.l (SC_PROLOGUE): Don't eat characters amongst
        ['"/] too eagerly.
        * tests/input.at (Torturing the Scanner): New.

Index: src/scan-gram.l
===================================================================
RCS file: /cvsroot/bison/bison/src/scan-gram.l,v
retrieving revision 1.4
diff -u -u -r1.4 scan-gram.l
--- src/scan-gram.l 11 Jun 2002 21:46:16 -0000 1.4
+++ src/scan-gram.l 12 Jun 2002 12:47:48 -0000
@@ -440,7 +440,7 @@
   "$"("<".*">")?(-?[0-9]+|"$") { handle_dollar (yytext); }
   "@"(-?[0-9]+|"$")            { handle_at (yytext); }
 
-  [^\[\]$/\'\"@\{\}\n\r]+ YY_OBS_GROW;
+  address@hidden/\'\"\{\}\n\r]+ YY_OBS_GROW;
   {eols}       YY_OBS_GROW; YY_LINES;
 
   /* A lose $, or /, or etc. */
@@ -471,7 +471,7 @@
     return PROLOGUE;
   }
 
-  [^\[\]%\n\r]+          YY_OBS_GROW;
+  [^%\[\]/\'\"\n\r]+     YY_OBS_GROW;
   "%"+[^%\}\n\r]+ YY_OBS_GROW;
   {eols}         YY_OBS_GROW; YY_LINES;
 
Index: tests/input.at
===================================================================
RCS file: /cvsroot/bison/bison/tests/input.at,v
retrieving revision 1.5
diff -u -u -r1.5 input.at
--- tests/input.at 11 Jun 2002 08:08:22 -0000 1.5
+++ tests/input.at 12 Jun 2002 12:47:48 -0000
@@ -1,5 +1,5 @@
 # Checking the output filenames.                    -*- Autotest -*-
-# Copyright 2002 Free Software Foundation, Inc.
+# Copyright (C) 2002 Free Software Foundation, Inc.
 
 # 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
@@ -19,6 +19,31 @@
 AT_BANNER([[Input Processing.]])
 
 # Mostly test that we are robust to mistakes.
+
+
+## ----------------------- ##
+## Torturing the Scanner.  ##
+## ----------------------- ##
+
+AT_SETUP([Torturing the Scanner])
+
+AT_DATA([input.y],
+[[%{
+/* This is seen in GCC: a %{ and %} in middle of a comment. */
+const char *foo = "So %{ and %} can be here.";
+%}
+/* %{ and %} can be here too. */
+
+%%
+exp: 'a';
+]])
+
+AT_CHECK([bison input.y])
+
+AT_CLEANUP
+
+
+
 
 ## ------------ ##
 ## Invalid $n.  ##