[Bug libstdc++/78713] [missed optimization] gcc doesn't use clobbers to optimize constructors

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78713

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |missed-optimization
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2016-12-09
          Component|tree-optimization           |libstdc++
     Ever confirmed|0                           |1

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
Depends on the size of the optional thing of course.  A libstdc++ issue, the
middle-end can not know it is allowed to clobber the destination here.