https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117163
--- Comment #6 from Paul Caprioli <paul at hpkfft dot com> --- One day, those older compilers will be considered ancient. Code written using AVX512 intrinsics isn't the most portable anyway, and programmers are always able to define their own macros (or just type a 0) if they want to support old compilers. A similar situation arises whenever a new feature is added to GCC--the new thing cannot be used if one wants to support older compilers. Yes, _MM_FROUND_TO_NEAREST_INT is 0. So is EXIT_SUCCESS. Neither one can be used with _mm512_add_round_ps(a, b, rounding) by someone with a sense of craftsmanship. This is the first patch I've submitted to GCC. I apologize for not knowing the proper tracking protocol. If there is anything more I can do, I welcome any advice, either here or via private email. Best regards, Paul