diff -r c63cb2d10d6d -r d22f29abeb42 mercurial/revlog.py
--- a/mercurial/revlog.py	Sat May 14 20:51:57 2016 +0900
+++ b/mercurial/revlog.py	Sun Apr 02 18:57:03 2017 -0700
@@ -444,7 +444,7 @@
         if l >= 0:
             return l
 
-        t = self.revision(rev)
+        t = self.revision(rev, raw=True)
         return len(t)
     size = rawsize