--- a/mercurial/cmdutil.py	Fri Aug 05 14:29:22 2016 +0200
+++ b/mercurial/cmdutil.py	Wed Mar 08 16:53:09 2017 -0800
@@ -201,7 +201,7 @@
                     newlyaddedandmodifiedfiles]
         backups = {}
         if tobackup:
-            backupdir = repo.join('record-backups')
+            backupdir = repo.vfs.join('record-backups')
             try:
                 os.mkdir(backupdir)
             except OSError as err:
@@ -3412,7 +3412,7 @@
             raise error.Abort(msg, hint=hint)
     for f, clearable, allowcommit, msg, hint in unfinishedstates:
         if clearable and repo.vfs.exists(f):
-            util.unlink(repo.join(f))
+            util.unlink(repo.vfs.join(f))
 
 afterresolvedstates = [
     ('graftstate',