diff -r 5ee9b78ce805 -r 88ad04bcdc74 mercurial/revset.py
--- a/mercurial/revset.py	Wed Oct 08 02:47:00 2014 -0700
+++ b/mercurial/revset.py	Wed Oct 08 02:47:24 2014 -0700
@@ -572,7 +572,7 @@
     """``children(set)``
     Child changesets of changesets in set.
     """
-    s = getset(repo, baseset(repo), x).set()
+    s = getset(repo, baseset(repo), x)
     cs = _children(repo, subset, s)
     return subset & cs