https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68267
--- Comment #2 from Markus Trippelsdorf <trippels at gcc dot gnu.org> --- (In reply to Andreas Schwab from comment #1) > Which target? This is probably BIGGEST_ALIGNMENT. x86_64-pc-linux-gnu. You're right it works fine with e.g -march=skylake. Since handling of anything bigger than BIGGEST_ALIGNMENT is implementation defined, this is not bug per se.