* xdisp.c (with_echo_area_buffer_unwind_data): Save window

start marker...
(unwind_with_echo_area_buffer): ...to restore it here.  This
is needed to ensure that...
(redisplay_window): ...both window markers are valid here,
which is verified by eassert.
* editfns.c (save_excursion_save): Do not assume that
selected_window always displays the buffer.

3 files changed, 26 insertions, 9 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 6698cfe0fcf..1b5259811b1 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,14 @@
+2013-03-28  Dmitry Antipov  <dmantipov@yandex.ru>
+
+        * xdisp.c (with_echo_area_buffer_unwind_data): Save window
+        start marker...
+        (unwind_with_echo_area_buffer): ...to restore it here.  This
+        is needed to ensure that...
+        (redisplay_window): ...both window markers are valid here,
+        which is verified by eassert.
+        * editfns.c (save_excursion_save): Do not assume that
+        selected_window always displays the buffer.
+
 2013-03-27  Stefan Monnier  <monnier@iro.umontreal.ca>
 
         * casetab.c (init_casetab_once): Don't abuse the ascii eqv table for
diff --git a/src/editfns.c b/src/editfns.c
index 2d87b8e0064..0ab7c143c99 100644
--- a/src/editfns.c
+++ b/src/editfns.c
@@ -846,7 +846,7 @@ save_excursion_save (void)
       ? Fcopy_marker (BVAR (current_buffer, mark), Qnil)
       : Qnil),
      /* Selected window if current buffer is shown in it, nil otherwise.  */
-     ((XBUFFER (XWINDOW (selected_window)->buffer) == current_buffer)
+     (EQ (XWINDOW (selected_window)->buffer, Fcurrent_buffer ())
       ? selected_window : Qnil),
      BVAR (current_buffer, mark_active));
 }
diff --git a/src/xdisp.c b/src/xdisp.c
index d42e53fc314..dff8f719c0d 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -9994,7 +9994,7 @@ with_echo_area_buffer_unwind_data (struct window *w)
   Vwith_echo_area_save_vector = Qnil;
 
   if (NILP (vector))
-    vector = Fmake_vector (make_number (7), Qnil);
+    vector = Fmake_vector (make_number (9), Qnil);
 
   XSETBUFFER (tmp, current_buffer); ASET (vector, i, tmp); ++i;
   ASET (vector, i, Vdeactivate_mark); ++i;
@@ -10006,10 +10006,12 @@ with_echo_area_buffer_unwind_data (struct window *w)
       ASET (vector, i, w->buffer); ++i;
       ASET (vector, i, make_number (marker_position (w->pointm))); ++i;
       ASET (vector, i, make_number (marker_byte_position (w->pointm))); ++i;
+      ASET (vector, i, make_number (marker_position (w->start))); ++i;
+      ASET (vector, i, make_number (marker_byte_position (w->start))); ++i;
     }
   else
     {
-      int end = i + 4;
+      int end = i + 6;
       for (; i < end; ++i)
         ASET (vector, i, Qnil);
     }
@@ -10032,16 +10034,18 @@ unwind_with_echo_area_buffer (Lisp_Object vector)
   if (WINDOWP (AREF (vector, 3)))
     {
       struct window *w;
-      Lisp_Object buffer, charpos, bytepos;
+      Lisp_Object buffer;
 
       w = XWINDOW (AREF (vector, 3));
       buffer = AREF (vector, 4);
-      charpos = AREF (vector, 5);
-      bytepos = AREF (vector, 6);
 
       wset_buffer (w, buffer);
       set_marker_both (w->pointm, buffer,
-                       XFASTINT (charpos), XFASTINT (bytepos));
+                       XFASTINT (AREF (vector, 5)),
+                       XFASTINT (AREF (vector, 6)));
+      set_marker_both (w->start, buffer,
+                       XFASTINT (AREF (vector, 7)),
+                       XFASTINT (AREF (vector, 8)));
     }
 
   Vwith_echo_area_save_vector = vector;
@@ -15231,12 +15235,14 @@ redisplay_window (Lisp_Object window, int just_this_one_p)
   SET_TEXT_POS (lpoint, PT, PT_BYTE);
   opoint = lpoint;
 
-  /* W must be a leaf window here.  */
-  eassert (!NILP (w->buffer));
 #ifdef GLYPH_DEBUG
   *w->desired_matrix->method = 0;
 #endif
 
+  /* Make sure that both W's markers are valid.  */
+  eassert (XMARKER (w->start)->buffer == buffer);
+  eassert (XMARKER (w->pointm)->buffer == buffer);
+
  restart:
   reconsider_clip_changes (w, buffer);