* net/tramp.el (tramp-handle-unhandled-file-name-directory): Return "/".

lisp/ChangeLog

@@ -2,6 +2,7 @@
 
 	* net/tramp.el (with-tramp-progress-reporter, tramp-call-process):
 	Add traces.
+	(tramp-handle-unhandled-file-name-directory): Return "/".
 
 2014-06-02  Wilson Snyder  <wsnyder@wsnyder.org>
 

lisp/net/tramp.el

@@ -3340,8 +3340,9 @@ User is always nil."
 (defun tramp-handle-unhandled-file-name-directory (_filename)
   "Like `unhandled-file-name-directory' for Tramp files."
   ;; With Emacs 23, we could simply return `nil'.  But we must keep it
-  ;; for backward compatibility.
-  (expand-file-name "~/"))
+  ;; for backward compatibility.  "~/" cannot be returned, because
+  ;; there might be machines without a HOME directory (like hydra).
+  "/")
 
 (defun tramp-handle-set-visited-file-modtime (&optional time-list)
   "Like `set-visited-file-modtime' for Tramp files."