https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65994
--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> --- CWG2038 : http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#2038 Looks like it is explicit that there should be a difference between C++11/14 and C++17 .... But I can't find a compiler which accepts this code for C++11 or C++14 modes ....
