https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65547
--- Comment #5 from Jonathan Wakely <redi at gcc dot gnu.org> --- And as has been documented forever, the way to get diagnostics for GNU extensions that contradict the ISO standard is the -pedantic switch: https://gcc.gnu.org/onlinedocs/gcc-4.9.2/gcc/Warning-Options.html#index-pedantic-279 There is no bug here.
