https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78762
John Keiser <john at johnkeiser dot com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |john at johnkeiser dot com --- Comment #17 from John Keiser <john at johnkeiser dot com> --- I can confirm that with -mavx2 and -march=haswell, this still happens. We see it in simdjson on https://github.com/lemire/simdjson/pull/315 . Fixed by `-mtune=haswell` or `-mno-avx256-split-unaligned-load`.