https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70832
--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> --- >clang++ 3.7 works clang 4.0 and above rejects both tests now with the same message as GCC. Are we sure this was not a clang bug which was fixed? Also ICC and MSVC rejects the code for the same reason too.