diff --git a/mercurial/branchmap.py b/mercurial/branchmap.py
--- a/mercurial/branchmap.py
+++ b/mercurial/branchmap.py
@@ -316,8 +316,6 @@ class revbranchcache(object):
             self._rbcsnameslen = len(bndata) # for verification before writing
             self._names = [encoding.tolocal(bn) for bn in bndata.split('\0')]
         except (IOError, OSError), inst:
-            repo.ui.debug("couldn't read revision branch cache names: %s\n" %
-                          inst)
             if readonly:
                 # don't try to use cache - fall back to the slow path
                 self.branchinfo = self._branchinfo
diff --git a/tests/test-casefolding.t b/tests/test-casefolding.t
--- a/tests/test-casefolding.t
+++ b/tests/test-casefolding.t
@@ -28,7 +28,6 @@ test case collision on rename (issue750)
   a
   committing manifest
   committing changelog
-  couldn't read revision branch cache names: * (glob)
   committed changeset 0:07f4944404050f47db2e5c5071e0e84e7a27bba9
 
 Case-changing renames should work:
diff --git a/tests/test-convert-svn-encoding.t b/tests/test-convert-svn-encoding.t
--- a/tests/test-convert-svn-encoding.t
+++ b/tests/test-convert-svn-encoding.t
@@ -53,7 +53,6 @@ Convert while testing all possible outpu
   source: svn:afeb9c47-92ff-4c0c-9f72-e1f6eb8ac9af/trunk@1
   converting: 0/6 revisions (0.00%)
   committing changelog
-  couldn't read revision branch cache names: * (glob)
   4 hello
   source: svn:afeb9c47-92ff-4c0c-9f72-e1f6eb8ac9af/trunk@2
   converting: 1/6 revisions (16.67%)