diff --git a/lisp/dom.el b/lisp/dom.el
index 42131073a04..091197a8f9d 100644
--- a/lisp/dom.el
+++ b/lisp/dom.el
@@ -25,6 +25,7 @@
 ;;; Code:
 
 (require 'cl-lib)
+(eval-when-compile (require 'subr-x))
 
 (defsubst dom-tag (node)
   "Return the NODE tag."