[Bug tree-optimization/65356] [meta-bug] Port tail-merge fixes to 4.9

[vries at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65356

vries at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|RESOLVED                    |ASSIGNED
   Last reconfirmed|                            |2016-01-25
         Resolution|FIXED                       |---
     Ever confirmed|0                           |1