https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94338
--- Comment #9 from Richard Biener <rguenth at gcc dot gnu.org> --- Btw, struct X { long a __attribute__((__aligned__(128))); long b __attribute__((__aligned__(128))); }; struct X A __attribute__((__aligned__(4))); is not diagnosed (this is what your testcase is, decomposed). I can't reproduce the diagnostics you describe in comment#5