--- a/mercurial/revset.py	Wed Sep 17 10:59:16 2014 -0700
+++ b/mercurial/revset.py	Wed Sep 17 19:52:34 2014 -0700
@@ -1167,7 +1167,7 @@
 
     o = set([_firstsrc(r) for r in args])
     o -= set([None])
-    return subset.filter(o.__contains__)
+    return subset & o
 
 def outgoing(repo, subset, x):
     """``outgoing([path])``