regex_executor.tcc (_DFSExecutor<>::_M_dfs): Fix wrong backup variable initialization.

2013-10-03  Tim Shen  <timshen91@gmail.com>

	* include/bits/regex_executor.tcc (_DFSExecutor<>::_M_dfs): Fix wrong
	backup variable initialization.

From-SVN: r203190

libstdc++-v3/ChangeLog

+2013-10-03  Tim Shen  <timshen91@gmail.com>
+
+	* include/bits/regex_executor.tcc (_DFSExecutor<>::_M_dfs): Fix wrong
+	backup variable initialization.
+
 2013-10-03  John Woolverton  <jdwoolverton@gmail.com>
 
 	PR libstdc++/58604

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;