diff --git a/lisp/progmodes/cc-mode.el b/lisp/progmodes/cc-mode.el
index 8dea599ed98..227a6af2a6b 100644
--- a/lisp/progmodes/cc-mode.el
+++ b/lisp/progmodes/cc-mode.el
@@ -257,7 +257,7 @@ control).  See \"cc-mode.el\" for more info."
 
   ;; Set up text conversion, for Emacs >= 30.0
   (when (boundp 'post-text-conversion-hook)
-    (add-hook 'post-text-conversion-hook #'c-post-text-conversion))
+    (add-hook 'post-text-conversion-hook #'c-post-text-conversion nil t))
 
   (unless new-style-init
     (c-init-language-vars-for 'c-mode)))