PR libstdc++/79980 fix target type of cast

	PR libstdc++/79980
	* src/c++11/codecvt.cc (to_integer(codecvt_mode)): Fix target type.

From-SVN: r246205

libstdc++-v3/ChangeLog

 2017-03-16  Jonathan Wakely  <jwakely@redhat.com>
 
+	PR libstdc++/79980
+	* src/c++11/codecvt.cc (to_integer(codecvt_mode)): Fix target type.
+
 	PR libstdc++/80041
 	* src/c++11/codecvt.cc (__codecvt_utf16_base<wchar_t>::do_out)
 	(__codecvt_utf16_base<wchar_t>::do_in): Convert char arguments to

libstdc++-v3/src/c++11/codecvt.cc

@@ -34,7 +34,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
   // The standard doesn't define these operators, which is annoying.
   static underlying_type<codecvt_mode>::type
   to_integer(codecvt_mode m)
-  { return static_cast<mode_t>(m); }
+  { return static_cast<underlying_type<codecvt_mode>::type>(m); }
 
   static codecvt_mode& operator&=(codecvt_mode& m, codecvt_mode n)
   { return m = codecvt_mode(to_integer(m) & to_integer(n)); }