https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61949
--- Comment #17 from Richard Biener <rguenth at gcc dot gnu.org> --- ./configure --target=i386-pc-solaris2.10 is not enough, with -O3 -msse2 and the preprocessed file I get md5_finish_ctx: ... call md5_process_block movl 12(%ebp), %eax addl $16, %esp movdqu (%ebx), %xmm0 movups %xmm0, (%eax) leal -12(%ebp), %esp popl %ebx popl %esi popl %edi popl %ebp ret thus the expected unaligned moves, also not from the stacak.