diff --git a/init.el b/init.el
index cccbe96..c082ee1 100644
--- a/init.el
+++ b/init.el
@@ -863,7 +863,9 @@ INFO plist."
   :config
   (add-hook 'prog-mode-hook
             (lambda ()
-              (which-func-mode)))
+              (if (fboundp 'which-function-mode)
+                  (which-function-mode)
+                (which-func-mode))))
   (setq which-func-unknown "∅"))
 
 (use-package ace-popup-menu