https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68484
--- Comment #1 from Marc Glisse <glisse at gcc dot gnu.org> --- -fno-strict-aliasing The intrinsic is implemented inline as: *(long long *)__P = ... which exposes the strict aliasing. I don't know how much we want to promise for those functions. It would be possible to use a may_alias typedef for long long, but I'll let someone else decide if we want to.