(add-hook): Use local local-variable-if-set-p.

diff --git a/lisp/subr.el b/lisp/subr.el
index b84e8ffc89b7c97cd75364d265e36f8e04f3733a..65a22d1f11619fcf54c8ee43c8fda76f6cd92506 100644 (file)
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -612,7 +612,7 @@ function, it is changed to a list of functions."
   (if (or local
          ;; Detect the case where make-local-variable was used on a hook
          ;; and do what we used to do.
-         (and (local-variable-p hook)
+         (and (local-variable-if-set-p hook)
               (not (memq t (symbol-value hook)))))
       ;; Alter the local value only.
       (or (if (consp function)