https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94771
--- Comment #4 from Bence Szabó <sbence92 at gmail dot com> --- Interesting, the t.f syntax is not allowed anymore even with MSVC: https://godbolt.org/z/YCK-mv msvc also doesn't list under extensions_ https://docs.microsoft.com/en-us/cpp/build/reference/microsoft-extensions-to-c-and-cpp?view=vs-2015 and some recent overview on ms extensions: https://stackoverflow.com/questions/56554567/what-does-the-ms-extensions-flag-do-exactly-with-gcc Is this a dinosaur that forgot to die?