http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60088
--- Comment #17 from Jouko Orava <jouko.orava at iki dot fi> --- I asked and received the details from Jacob Abel off-list, to find out if this bug #60088 is related to bug #50201. They do not seem to be. The instruction causing the segfault in this bug #60088 is 66 0f 7f 02 movdqa %xmm0,(%edx) which requires %edx to be aligned to a 16 byte boundary, but %edx is 0x81325c8, unaligned. Thus, segfault. Why this occurs with -mavx but not without, I do not know. In short, the segfault is due to 8-byte aligned access, where 16-byte alignment is required. Perhaps this bug is related to bug #56564 ?