https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87581
Jakub Jelinek <jakub at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |RESOLVED CC| |jakub at gcc dot gnu.org Resolution|--- |INVALID --- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> --- It is not a problem, your program is simply invalid. On partial strict alignment architectures like x86 you sometimes get away with that, but that doesn't mean it is valid, it is still undefined behavior. As has been said, use -fsanitize=undefined to detect these cases and fix them.