diff --git a/mercurial/error.py b/mercurial/error.py
--- a/mercurial/error.py
+++ b/mercurial/error.py
@@ -48,7 +48,7 @@
 
 
 class RevlogError(StorageError):
-    __bytes__ = _tobytes
+    pass
 
 
 class SidedataHashError(RevlogError):