[Bug middle-end/90345] too pessimistic check whether pointer may alias a local variable

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90345

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2019-05-06
     Ever confirmed|0                           |1

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
Actually GCC knows this but 'carry' escapes here:

    if (carry)
    {
        a.push_back(carry);
        //a.push_back(uint32_t(carry));
    }

and thus a _can_ point to it since points-to analysis isn't flow-sensitive.

An old "imperfect" idea is to virtually "outline" the function body at
SESE region boundaries to make points-to analysis somewhat flow-sensitive
(not actually at BB boundaries because we do not want to consider backedges
here).