https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115990
--- Comment #13 from Richard Biener <rguenth at gcc dot gnu.org> --- Note that -ffast-math isn't in any way better, it doesn't suggest wrong-math either. It possibly should have been -fno-ieee-conformant-math or so. clang for example enables -fno-semantic-interposition by default which breaks valid programs. With GCC it's part of -Ofast.