(add-to-invisibility-spec): If it was t, start it out at (t).

diff --git a/lisp/subr.el b/lisp/subr.el
index 093812d13c51d4edb5aa5e2312273c326cca036b..c0e0ea61ef3bc15eba6658b1e070089f6b1f1df4 100644 (file)
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -1881,12 +1881,10 @@ from `standard-syntax-table' otherwise."
   "Add elements to `buffer-invisibility-spec'.
 See documentation for `buffer-invisibility-spec' for the kind of elements
 that can be added."
-  (cond
-   ((or (null buffer-invisibility-spec) (eq buffer-invisibility-spec t))
-       (setq buffer-invisibility-spec (list arg)))
-   (t
-    (setq buffer-invisibility-spec
-         (cons arg buffer-invisibility-spec)))))
+  (if (eq buffer-invisibility-spec t)
+      (setq buffer-invisibility-spec (list t)))
+  (setq buffer-invisibility-spec
+       (cons arg buffer-invisibility-spec)))
 
 (defun remove-from-invisibility-spec (arg)
   "Remove elements from `buffer-invisibility-spec'."