2 files changed, 7 insertions, 2 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index a6e04ca25db..394e082ecc8 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,5 +1,8 @@
 2012-03-05  Leo Liu  <sdl.web@gmail.com>
 
+        * simple.el (backward-delete-char-untabify): Constrain point to
+        field (Bug#10939).
+
         * eshell/em-cmpl.el (eshell-cmpl-initialize): Fix shift-tab key.
 
 2012-03-05  Chong Yidong  <cyd@gnu.org>
diff --git a/lisp/simple.el b/lisp/simple.el
index 2b4651ba697..45daf99f614 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -3463,8 +3463,10 @@ and KILLP is t if a prefix arg was specified."
                      ((eq backward-delete-char-untabify-method 'all)
                       " \t\n\r")))
          (n (if skip
-                (let ((wh (- (point) (save-excursion (skip-chars-backward skip)
-                                                     (point)))))
+                (let* ((oldpt (point))
+                       (wh (- oldpt (save-excursion
+                                      (skip-chars-backward skip)
+                                      (constrain-to-field nil oldpt)))))
                   (+ arg (if (zerop wh) 0 (1- wh))))
               arg)))
     ;; Avoid warning about delete-backward-char