(dired-find-buffer-nocreate): Avoid error if dired-directory is nil.

diff --git a/lisp/dired.el b/lisp/dired.el
index d658960a35e576a5f5b04256f37370e77a20dddf..d15d80411f113c44402fc815202d4bb120d6cacb 100644 (file)
--- a/lisp/dired.el
+++ b/lisp/dired.el
@@ -589,6 +589,7 @@ If DIRNAME is already in a dired buffer, that buffer is used without refresh."
        (save-excursion
          (set-buffer (cdr (car blist)))
          (if (and (eq major-mode mode)
+                  dired-directory  ;; nil during find-alternate-file
                   (equal dirname
                          (expand-file-name
                           (if (consp dired-directory)