--- a/mercurial/revset.py	Thu Jun 11 11:42:46 2015 -0700
+++ b/mercurial/revset.py	Thu Jun 11 19:02:24 2015 -0700
@@ -622,9 +622,7 @@
         return baseset()
     cs = set()
     pr = repo.changelog.parentrevs
-    # XXX this should be 'parentset.min()' assuming 'parentset' is a smartset
-    # (and if it is not, it should.)
-    minrev = min(parentset)
+    minrev = parentset.min()
     for r in narrow:
         if r <= minrev:
             continue