(momentary-string-display): Avoid modifying the undo list.

diff --git a/lisp/subr.el b/lisp/subr.el
index 5a08278241fdf24104ad4a6399b6ac5412d91e20..50321c3d666b1657198ab4d1ad0b15222ebf394d 100644 (file)
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -600,6 +600,8 @@ Display MESSAGE (optional fourth arg) in the echo area.
 If MESSAGE is nil, instructions to type EXIT-CHAR are displayed there."
   (or exit-char (setq exit-char ?\ ))
   (let ((buffer-read-only nil)
+       ;; Don't modify the undo list at all.
+       (buffer-undo-list t)
        (modified (buffer-modified-p))
        (name buffer-file-name)
        insert-end)