http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55842
--- Comment #3 from Marc Glisse <glisse at gcc dot gnu.org> 2013-01-01 18:30:52 UTC --- template <class=void> struct number { number() noexcept(noexcept(0)) { } }; const int z=__has_nothrow_constructor(number<>);