2 files changed, 14 insertions, 1 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index ef84324c9d9..441a4c00be8 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,8 @@
+2012-04-09  Eli Zaretskii  <eliz@gnu.org>
+
+        * xdisp.c (find_last_unchanged_at_beg_row): Don't consider a row
+        "unchanged" if its end.pos is beyond ZV.  (Bug#11199)
+
 2012-04-09  Jan Djärv  <jan.h.d@swipnet.se>
 
         * nsterm.m (constrainFrameRect): Always constrain when there is only
diff --git a/src/xdisp.c b/src/xdisp.c
index dcd14a1792a..07aad31abf1 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -16602,7 +16602,15 @@ find_last_unchanged_at_beg_row (struct window *w)
              continued.  */
           && !(MATRIX_ROW_END_CHARPOS (row) == first_changed_pos
                && (row->continued_p
-                   || row->exact_window_width_line_p)))
+                   || row->exact_window_width_line_p))
+          /* If ROW->end is beyond ZV, then ROW->end is outdated and
+             needs to be recomputed, so don't consider this row as
+             unchanged.  This happens when the last line was
+             bidi-reordered and was killed immediately before this
+             redisplay cycle.  In that case, ROW->end stores the
+             buffer position of the first visual-order character of
+             the next row, which is now beyond ZV.  */
+          && CHARPOS (row->end.pos) <= ZV)
         row_found = row;
 
       /* Stop if last visible row.  */