https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106646
--- Comment #1 from Joseph S. Myers <jsm28 at gcc dot gnu.org> --- Enabled for C2x (i.e. stopped -pedantic diagnosing it) with commit d7c3000147c1d8090f66a2baf4623d2c0dfe8eb6 - C++ will presumably want to adjust the diagnostics as well as enabling for relevant C++ versions and adding associated tests.