Merge zizzer.eecs.umich.edu:/z/m5/Bitkeeper/newmem

into  zizzer.eecs.umich.edu:/.automount/zooks/y/ksewell/research/m5-sim/newmem-o3

--HG--
extra : convert_revision : 90717b492139428e0c48be35a6bda45960c61086

src/cpu/o3/commit_impl.hh

@@ -569,6 +569,9 @@ DefaultCommit<Impl>::tick()
         return;
     }
 
+    if ((*activeThreads).size() <= 0)
+        return;
+
     list<unsigned>::iterator threads = (*activeThreads).begin();
 
     // Check if any of the threads are done squashing.  Change the