--- a/mercurial/context.py	Sat Mar 14 22:34:27 2015 +0900
+++ b/mercurial/context.py	Thu Mar 19 19:52:23 2015 -0700
@@ -913,6 +913,8 @@
         introrev = self.introrev()
         if self.rev() != introrev:
             base = self.filectx(self.filenode(), changeid=introrev)
+            ac = self._repo.changelog.ancestors([introrev], inclusive=True)
+            base._ancestrycontext = ac
 
         # This algorithm would prefer to be recursive, but Python is a
         # bit recursion-hostile. Instead we do an iterative