https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103555
--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> --- Both ICC and MSVC reject it in the same way GCC rejects it so I am 99% sure that there is either a defect report against the C++ standard or http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2020/p1787r6.html changes the way some names are found here.
