diff -r edaa40dc5fe5 -r 5ccd791344f3 mercurial/manifest.py
--- a/mercurial/manifest.py	Fri Sep 21 21:44:27 2018 -0400
+++ b/mercurial/manifest.py	Tue Sep 18 15:15:24 2018 -0700
@@ -1609,7 +1609,7 @@
     of the list of files in the given commit. Consumers of the output of this
     class do not care about the implementation details of the actual manifests
     they receive (i.e. tree or flat or lazily loaded, etc)."""
-    def __init__(self, opener, repo):
+    def __init__(self, opener, repo, rootstore):
         usetreemanifest = False
         cachesize = 4
 
@@ -1620,7 +1620,7 @@
 
         self._treemanifests = usetreemanifest
 
-        self._rootstore = repo._constructmanifest()
+        self._rootstore = rootstore
         self._rootstore._setupmanifestcachehooks(repo)
         self._narrowmatch = repo.narrowmatch()