https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98202
--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> --- With GCC 13 it's now a pedwarn: f128.cc:1:1: warning: 'f128' or 'F128' suffix on floating constant only available with '-std=c++2b' or '-std=gnu++2b' [-Wpedantic]
