* lisp/subr.el (find-tag-default-as-regexp): Return nil if `tag' is nil.

Fixes: debbugs:14390

2 files changed, 6 insertions, 1 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index d39c434cb6f..5b2c28d97a1 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,8 @@
+2013-05-14  Juri Linkov  <juri@jurta.org>
+
+        * subr.el (find-tag-default-as-regexp): Return nil if `tag' is nil.
+        (Bug#14390)
+
 2013-05-14  Glenn Morris  <rgm@gnu.org>
 
         * progmodes/f90.el (f90-imenu-generic-expression):
diff --git a/lisp/subr.el b/lisp/subr.el
index 4871f3733f9..177e9a84a58 100644
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -2738,7 +2738,7 @@ symbol at point exactly."
                    (get major-mode 'find-tag-default-function)
                    'find-tag-default))
          (tag (funcall tagf)))
-    (cond ((not tag))
+    (cond ((null tag) nil)
           ((eq tagf 'find-tag-default)
            (format "\\_<%s\\_>" (regexp-quote tag)))
           (t (regexp-quote tag)))))