Original patch from: gentoo/src/patchsets/glibc/2.9/0052_all_glibc-2.9-regex-BZ9697.patch

 -= BEGIN original header =-

 http://sourceware.org/ml/libc-alpha/2009-01/msg00005.html

 From ea8ca0dfcbf2721bcf2c08ce3c01d5764b827572 Mon Sep 17 00:00:00 2001

 From: Ulrich Drepper <drepper@redhat.com>

 Date: Thu, 8 Jan 2009 00:42:28 +0000

 Subject: [PATCH] (re_compile_fastmap_iter): Rewrite COMPLEX_BRACKET handling.

 -= END original header =-

 diff -durN glibc-2_9.orig/posix/regcomp.c glibc-2_9/posix/regcomp.c

 --- glibc-2_9.orig/posix/regcomp.c	2008-05-15 05:07:21.000000000 +0200

 +++ glibc-2_9/posix/regcomp.c	2009-02-02 22:00:41.000000000 +0100

 @@ -350,47 +350,67 @@

  #ifdef RE_ENABLE_I18N

        else if (type == COMPLEX_BRACKET)

  	{

 -	  int i;

  	  re_charset_t *cset = dfa->nodes[node].opr.mbcset;

 -	  if (cset->non_match || cset->ncoll_syms || cset->nequiv_classes

 -	      || cset->nranges || cset->nchar_classes)

 -	    {

 +	  int i;

 +

  # ifdef _LIBC

 -	      if (_NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES) != 0)

 +	  /* See if we have to try all bytes which start multiple collation

 +	     elements.

 +	     e.g. In da_DK, we want to catch 'a' since "aa" is a valid

 +		  collation element, and don't catch 'b' since 'b' is

 +		  the only collation element which starts from 'b' (and

 +		  it is caught by SIMPLE_BRACKET).  */

 +	      if (_NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES) != 0

 +		  && (cset->ncoll_syms || cset->nranges))

  		{

 -		  /* In this case we want to catch the bytes which are

 -		     the first byte of any collation elements.

 -		     e.g. In da_DK, we want to catch 'a' since "aa"

 -			  is a valid collation element, and don't catch

 -			  'b' since 'b' is the only collation element

 -			  which starts from 'b'.  */

  		  const int32_t *table = (const int32_t *)

  		    _NL_CURRENT (LC_COLLATE, _NL_COLLATE_TABLEMB);

  		  for (i = 0; i < SBC_MAX; ++i)

  		    if (table[i] < 0)

  		      re_set_fastmap (fastmap, icase, i);

  		}

 -# else

 -	      if (dfa->mb_cur_max > 1)

 -		for (i = 0; i < SBC_MAX; ++i)

 -		  if (__btowc (i) == WEOF)

 -		    re_set_fastmap (fastmap, icase, i);

 -# endif /* not _LIBC */

 -	    }

 -	  for (i = 0; i < cset->nmbchars; ++i)

 +# endif /* _LIBC */

 +

 +	  /* See if we have to start the match at all multibyte characters,

 +	     i.e. where we would not find an invalid sequence.  This only

 +	     applies to multibyte character sets; for single byte character

 +	     sets, the SIMPLE_BRACKET again suffices.  */

 +	  if (dfa->mb_cur_max > 1

 +	      && (cset->nchar_classes || cset->non_match

 +# ifdef _LIBC

 +		  || cset->nequiv_classes

 +# endif /* _LIBC */

 +		 ))

  	    {

 -	      char buf[256];

 -	      mbstate_t state;

 -	      memset (&state, '\0', sizeof (state));

 -	      if (__wcrtomb (buf, cset->mbchars[i], &state) != (size_t) -1)

 -		re_set_fastmap (fastmap, icase, *(unsigned char *) buf);

 -	      if ((bufp->syntax & RE_ICASE) && dfa->mb_cur_max > 1)

 +	      unsigned char c = 0;

 +	      do

  		{

 -		  if (__wcrtomb (buf, towlower (cset->mbchars[i]), &state)

 -		      != (size_t) -1)

 -		    re_set_fastmap (fastmap, 0, *(unsigned char *) buf);

 +		  mbstate_t mbs;

 +		  memset (&mbs, 0, sizeof (mbs));

 +		  if (__mbrtowc (NULL, (char *) &c, 1, &mbs) == (size_t) -2)

 +		    re_set_fastmap (fastmap, false, (int) c);

  		}

 +	      while (++c != 0);

  	    }

 +

 +	  else

 +	    {

 +	      /* ... Else catch all bytes which can start the mbchars.  */

 +	      for (i = 0; i < cset->nmbchars; ++i)

 +		{

 +		  char buf[256];

 +		  mbstate_t state;

 +		  memset (&state, '\0', sizeof (state));

 +		  if (__wcrtomb (buf, cset->mbchars[i], &state) != (size_t) -1)

 +		    re_set_fastmap (fastmap, icase, *(unsigned char *) buf);

 +		  if ((bufp->syntax & RE_ICASE) && dfa->mb_cur_max > 1)

 +		    {

 +		      if (__wcrtomb (buf, towlower (cset->mbchars[i]), &state)

 +			  != (size_t) -1)

 +			re_set_fastmap (fastmap, false, *(unsigned char *) buf);

 +		    }

 + 		}

 + 	    }

  	}

  #endif /* RE_ENABLE_I18N */

        else if (type == OP_PERIOD