diff --git a/lisp/files.el b/lisp/files.el
index 5cf294ab54c..6861e2a83a8 100644
--- a/lisp/files.el
+++ b/lisp/files.el
@@ -1232,7 +1232,8 @@ if you wish to pass an empty string as the argument."
 	      (rename-buffer new-name t))))
     (setq buffer-backed-up nil)
     (clear-visited-file-modtime)
-    (setq buffer-file-truename (abbreviate-file-name truename))
+    (if truename
+	(setq buffer-file-truename (abbreviate-file-name truename)))
     (setq buffer-file-number
 	  (if filename
 	      (nth 10 (file-attributes buffer-file-name))