--- a/mercurial/branchmap.py	Thu Oct 11 03:15:04 2018 +0200
+++ b/mercurial/branchmap.py	Fri Aug 31 19:58:41 2018 +0100
@@ -296,7 +296,6 @@
             # This have been tested True on all internal usage of this function.
             # run it again in case of doubt
             # assert not (set(bheadrevs) & set(newheadrevs))
-            newheadrevs.sort()
             bheadset.update(newheadrevs)
 
             # This prunes out two kinds of heads - heads that are superseded by