[Bug middle-end/32327] [4.2 Regression] Incorrect stack sharing causing removal of live code

["pinskia at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #5 from pinskia at gcc dot gnu dot org  2007-06-13 21:42 -------
(In reply to comment #2)
> The address of dest has been passed to memcpy() and the alias analysis
> considers the varaible to escape. So potentially foo() can see the value of
> dest if memcpy() stash the pointer somewhere. This is impossible but the
> compiler cannot prove this so it has to be conservative and treat foo() as a
> potential reader of dest.
We remove the call to memcpy (in 4.2) in .064t.fab and then alias5 should have
changed it (dest) to be non ADDRESSABLE but it is not for some reason.

I think may_alias is messed up in 4.2.0.  Also sink maybe should not be sinking
stores.


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to work|4.3.0                       |4.3.0 4.1.1
            Summary|Incorrect stack sharing     |[4.2 Regression] Incorrect
                   |causing removal of live code|stack sharing causing
                   |                            |removal of live code
   Target Milestone|---                         |4.2.1


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32327