diff -r c21342159fad -r 43f664bf2e1e mercurial/revset.py
--- a/mercurial/revset.py	Fri Oct 03 20:12:02 2014 -0700
+++ b/mercurial/revset.py	Fri Oct 03 20:43:48 2014 -0700
@@ -2622,7 +2622,7 @@
         """
         self._gen = gen
         self._cache = {}
-        self._genlist = baseset([])
+        self._genlist = []
         self._finished = False
         if iterasc is not None:
             if iterasc: