--- a/mercurial/revlog.py	Thu Apr 06 20:13:09 2006 -0400
+++ b/mercurial/revlog.py	Sat Apr 08 20:08:06 2006 -0400
@@ -822,6 +822,7 @@
             return
         if not fp:
             fp = self.opener(self.indexfile, 'r')
+            fp.seek(0, 2)
         size = fp.tell()
         if size < 131072:
             return