// Not necessary in Snow Leopard (si_code will be != 0).
	if GOOS == "darwin" && sig == _SIGFPE && gp.sigcode0 == 0 {
		pc := (*[4]byte)(unsafe.Pointer(gp.sigpc))
		i := 0
		if pc[i]&0xF0 == 0x40 { // 64-bit REX prefix
			i++
		} else if pc[i] == 0x66 { // 16-bit instruction prefix
			i++
		}
		if pc[i] == 0xF6 || pc[i] == 0xF7 {
			gp.sigcode0 = _FPE_INTDIV
		}
	}

	pc := uintptr(c.rip())