diff --git a/lisp/org-compat.el b/lisp/org-compat.el
index 5a9fe107d..e8af6128b 100644
--- a/lisp/org-compat.el
+++ b/lisp/org-compat.el
@@ -60,7 +60,7 @@
   (defalias 'gui-get-selection 'x-get-selection)
 
   ;; From "files.el"
-  (defsubst directory-name-p (name)
+  (defun directory-name-p (name)
     "Return non-nil if NAME ends with a directory separator character."
     (let ((len (length name))
 	  (lastc ?.))