diff --git a/mercurial/discovery.py b/mercurial/discovery.py
--- a/mercurial/discovery.py
+++ b/mercurial/discovery.py
@@ -238,8 +238,14 @@ def _oldheadssummary(repo, remoteheads, 
         unsynced = set()
     return {None: (oldheads, newheads, unsynced)}
 
-def _nowarnheads(repo, remote, newbookmarks):
+def _nowarnheads(pushop):
     # Compute newly pushed bookmarks. We don't warn about bookmarked heads.
+
+    # internal config: bookmarks.pushing
+    newbookmarks = pushop.ui.configlist('bookmarks', 'pushing')
+
+    repo = pushop.repo.unfiltered()
+    remote = pushop.remote
     localbookmarks = repo._bookmarks
     remotebookmarks = remote.listkeys('bookmarks')
     bookmarkedheads = set()
@@ -268,9 +274,6 @@ def checkheads(pushop):
     newbranch = pushop.newbranch
     inc = bool(pushop.incoming)
 
-    # internal config: bookmarks.pushing
-    newbookmarks = pushop.ui.configlist('bookmarks', 'pushing')
-
     # Check for each named branch if we're creating new remote heads.
     # To be a remote head after push, node must be either:
     # - unknown locally
@@ -296,7 +299,7 @@ def checkheads(pushop):
                                 " new remote branches"))
 
     # 2. Find heads that we need not warn about
-    nowarnheads = _nowarnheads(repo, remote, newbookmarks)
+    nowarnheads = _nowarnheads(pushop)
 
     # 3. Check for new heads.
     # If there are more heads after the push than before, a suitable