http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55783
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> 2012-12-22 00:06:50 UTC --- "With -std=c++11, -Wno-narrowing suppresses the diagnostic required by the standard. Note that this does not affect the meaning of well-formed code; narrowing conversions are still considered ill-formed in SFINAE context. "
