commit 63aac30378dfe58e52cc19dc2678af3e36ea38b3
Author: tim <timshen91@gmail.com>
Date:   Thu Oct 3 13:25:33 2013 -0400

    2013-10-03  Tim Shen  <timshen91@gmail.com>
    
    	* include/bits/regex_executor.tcc (_DFSExecutor<>::_M_dfs): Fix wrong
    	backup variable initialization.

diff --git a/libstdc++-v3/include/bits/regex_executor.tcc b/libstdc++-v3/include/bits/regex_executor.tcc
index 3a40800..60ba952 100644
--- a/libstdc++-v3/include/bits/regex_executor.tcc
+++ b/libstdc++-v3/include/bits/regex_executor.tcc
@@ -66,7 +66,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	  if (!_M_cur_results[__state._M_subexpr].matched
 	      || _M_cur_results[__state._M_subexpr].first != __current)
 	    {
-	      auto __back = __current;
+	      auto __back = _M_cur_results[__state._M_subexpr].first;
 	      _M_cur_results[__state._M_subexpr].first = __current;
 	      __ret = _M_dfs(__state._M_next);
 	      _M_cur_results[__state._M_subexpr].first = __back;