--- a/mercurial/repair.py	Sat Feb 07 12:49:30 2015 -0800
+++ b/mercurial/repair.py	Tue Mar 10 16:25:10 2015 -0400
@@ -137,6 +137,7 @@
     # create a changegroup for all the branches we need to keep
     backupfile = None
     vfs = repo.vfs
+    node = nodelist[-1]
     if backup:
         backupfile = _bundle(repo, stripbases, cl.heads(), node, topic)
         repo.ui.status(_("saved backup bundle to %s\n") %