(visit-tags-table-buffer): Don't look in list for tags-file-name if nil.

1 files changed, 2 insertions, 1 deletions

diff --git a/lisp/progmodes/etags.el b/lisp/progmodes/etags.el
index 8ffa931592b..04932d29c4e 100644
--- a/lisp/progmodes/etags.el
+++ b/lisp/progmodes/etags.el
@@ -365,7 +365,8 @@ Returns t if it visits a tags table, or nil if there are no more in the list."
                                                            tags-table-list)))
                 ;; Fourth, use the user variable tags-file-name, if it is not
                 ;; already in tags-table-list.
-                (and (not (tags-table-list-member tags-file-name))
+                (and tags-file-name
+                     (not (tags-table-list-member tags-file-name))
                      tags-file-name)
                 ;; Fifth, use the user variable giving the table list.
                 (car tags-table-list)