(font-lock-hack-keywords): Turn off undo generation.

(font-lock-unfontify-region. font-lock-fontify-region): Likewise.

diff --git a/lisp/font-lock.el b/lisp/font-lock.el
index 5c23041c3a6212e9a25838af90282d454a78e153..a737e0452f27cc0d97cace39b2de045b4d2accc1 100644 (file)
--- a/lisp/font-lock.el
+++ b/lisp/font-lock.el
@@ -335,6 +335,8 @@ the face is also set; its value is the face name."
       (beginning-of-line)
       (if loudly (message "Fontifying %s... (syntactically...)" (buffer-name)))
       (let ((buffer-read-only nil)
+           ;; Suppress all undo activity.
+           (buffer-undo-list t)
            (modified (buffer-modified-p))
            (cstart (if comment-start-skip
                        (concat "\\s\"\\|" comment-start-skip)
@@ -449,6 +451,7 @@ the face is also set; its value is the face name."
 
 (defun font-lock-unfontify-region (beg end)
   (let ((modified (buffer-modified-p))
+       (buffer-undo-list t)
        (buffer-read-only nil))
     (remove-text-properties beg end '(face nil))
     (set-buffer-modified-p modified)))
@@ -491,6 +494,7 @@ the face is also set; its value is the face name."
        (keywords font-lock-keywords)
        (count 0)
        (buffer-read-only nil)
+       (buffer-undo-list t)
        (modified (buffer-modified-p))
        (old-syntax (syntax-table))
        (bufname (buffer-name)))