https://gcc.gnu.org/bugzilla/show_bug.cgi?id=54412
--- Comment #37 from Eric Botcazou <ebotcazou at gcc dot gnu.org> --- > If the Windows ABI doesn't align stack or not as much as gcc assumes, then a > fix would ensure only automatic vars on Windows are accessed always using > unaligned vector instructions provided dynamic stack realignment is not an > option. It's classical double-word alignment, i.e. 16 bytes, and AVX requires 32 bytes. The implementation of dynamic stack realignment is too much of a kludge to be safely used on Windows IMO so, yes, the way out is probably unaligned vector instructions.
