1 files changed, 1 insertions, 5 deletions

diff --git a/lisp/derived.el b/lisp/derived.el
index d27c2b333f1..6db92e85408 100644
--- a/lisp/derived.el
+++ b/lisp/derived.el
@@ -331,11 +331,7 @@ be automatic inheritance."
 (defun derived-mode-merge-syntax-tables (old new)
   "Merge an old syntax table into a new one.
 Where the new table already has an entry, nothing is copied from the old one."
-  (map-char-table
-   (function (lambda (key value)
-               (or (char-table-range new key)
-                   (set-char-table-range new key value))))
-   old))
+  (set-char-table-parent new old))
 
 ;; Merge an old abbrev table into a new one.
 ;; This function requires internal knowledge of how abbrev tables work,