https://gcc.gnu.org/bugzilla/show_bug.cgi?id=17308
--- Comment #23 from Andrew Pinski <pinskia at gcc dot gnu.org> --- The patch which would have "fixed" this was reverted as there was too many false positives and that happens when you do optimization based warnings ... I don't know if we want to keep this open or close this as won't fix though. It has been 6 years since this was tried too and we still most likely have just as many false positives as before even. I also suspect many of these new warnings we are doing in recent years really should not be part of -Wall because of how many false positives we have. GCC has been getting a recent attention because of the false positives warnings too.
