[Bug tree-optimization/39207] [4.4 Regression] Strict aliasing warnings in libstdc++ headers

[rguenth at gcc dot gnu dot org]

------- Comment #6 from rguenth at gcc dot gnu dot org  2009-02-17 10:41 -------
This warning is only emitted if points-to analysis pruned the points-to set
to empty.  Thus, the pointer as far as PTA is concerned does not point to
anything.  On alias-improvements branch this results in stores and loads from
it vanishing.  On the trunk we fall back to pt_anything in this case.

Generally the warning hints at real problems, either in the compiler or in
user code.  There are known problems with boost and its interesting use of
placement new (we still do not handle placement new properly).  I will have
a look here.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |rguenth at gcc dot gnu dot
                   |dot org                     |org
             Status|UNCONFIRMED                 |ASSIGNED
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2009-02-17 10:41:14
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39207