The most recent instance, OOPS-1979MPJ1 appears to be due to attempting to perform a merge into the empty tree. While bzr may not do this, the failure is clearly a bug in bzrlib caused by the merge code assuming that the tree has a root.
The most recent instance, OOPS-1979MPJ1 appears to be due to attempting to perform a merge into the empty tree. While bzr may not do this, the failure is clearly a bug in bzrlib caused by the merge code assuming that the tree has a root.