From 3fca11d78cfa1fec6199936d57871b9db08226ab Mon Sep 17 00:00:00 2001
From: Paolo Bonzini <bonzini@gnu.org>
Date: Thu, 29 Apr 2010 17:13:32 +0200
Subject: [PATCH 2/2] fall back to glibc matcher if a MBCSET is found

This patch works around the performance problems of multibyte grep
upstream.

For UTF-8 it should trigger only in the presence of MBCSET, e.g. [a-z].

For other character sets all brackets and `.` as well will trigger it.
---
 src/dfa.c |    9 +++++++++
 1 files changed, 9 insertions(+), 0 deletions(-)

diff --git a/src/dfa.c b/src/dfa.c
index e13c361..523fe05 100644
--- a/src/dfa.c
+++ b/src/dfa.c
@@ -2927,6 +2927,15 @@ dfaexec (struct dfa *d, char const *begin, char *end,
 		continue;
 	      }
 
+	    if (backref)
+              {
+                *backref = 1;
+                free(mblen_buf);
+                free(inputwcs);
+                *end = saved_end;
+                return (char *) p;
+              }
+
 	    /* Can match with a multibyte character (and multi character
 	       collating element).  Transition table might be updated.  */
 	    s = transit_state(d, s, &p);
-- 
1.6.6.1