* src/xdisp.c (redisplay_internal): Don't call set_window_update_flags.

Set invisible frames's `redisplay' when a full redisplay is requested.
(redisplay_window): Set must_be_updated_p instead.
(redisplay_mode_lines): Don't set must_be_updated_p any more.
(display_mode_lines): Set it here instead.
* src/dispextern.h (set_window_update_flags): Remove.
* src/dispnew.c (set_window_update_flags): Remove `b' argument; make static.

Fixes: debbugs:15999

6 files changed, 97 insertions, 85 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index a626c2b1963..058597586e5 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,15 @@
+2013-11-30  Stefan Monnier  <monnier@iro.umontreal.ca>
+
+        * xdisp.c (redisplay_internal): Don't call set_window_update_flags.
+        Set invisible frames's `redisplay' when a full redisplay is requested.
+        (redisplay_window): Set must_be_updated_p instead (bug#15999).
+        (redisplay_mode_lines): Don't set must_be_updated_p any more.
+        (display_mode_lines): Set it here instead.
+
+        * dispnew.c (set_window_update_flags): Remove `b' argument; make static.
+
+        * dispextern.h (set_window_update_flags): Remove.
+
 2013-11-29  Stefan Monnier  <monnier@iro.umontreal.ca>
 
         * fns.c (internal_equal): Add a hash_table argument to handle cycles.
diff --git a/src/dispextern.h b/src/dispextern.h
index d40febd207a..6f162316242 100644
--- a/src/dispextern.h
+++ b/src/dispextern.h
@@ -3462,7 +3462,6 @@ void blank_row (struct window *, struct glyph_row *, int);
 void clear_glyph_matrix_rows (struct glyph_matrix *, int, int);
 void clear_glyph_row (struct glyph_row *);
 void prepare_desired_row (struct glyph_row *);
-void set_window_update_flags (struct window *, struct buffer *, bool);
 void update_single_window (struct window *, bool);
 void do_pending_window_change (bool);
 void change_frame_size (struct frame *, int, int, bool, bool, bool);
diff --git a/src/dispnew.c b/src/dispnew.c
index 3207f4a0018..b68cc2e54f8 100644
--- a/src/dispnew.c
+++ b/src/dispnew.c
@@ -97,6 +97,7 @@ static bool scrolling (struct frame *);
 static void set_window_cursor_after_update (struct window *);
 static void adjust_frame_glyphs_for_window_redisplay (struct frame *);
 static void adjust_frame_glyphs_for_frame_redisplay (struct frame *);
+static void set_window_update_flags (struct window *w, bool on_p);
 
 /* True means last display completed.  False means it was preempted.  */
 
@@ -2944,8 +2945,8 @@ redraw_frame (struct frame *f)
   /* Mark all windows as inaccurate, so that every window will have
      its redisplay done.  */
   mark_window_display_accurate (FRAME_ROOT_WINDOW (f), 0);
-  set_window_update_flags (XWINDOW (FRAME_ROOT_WINDOW (f)), NULL, 1);
-  f->garbaged = 0;
+  set_window_update_flags (XWINDOW (FRAME_ROOT_WINDOW (f)), true);
+  f->garbaged = false;
 }
 
 DEFUN ("redraw-frame", Fredraw_frame, Sredraw_frame, 0, 1, 0,
@@ -3029,7 +3030,7 @@ update_frame (struct frame *f, bool force_p, bool inhibit_hairy_id_p)
               Lisp_Object tem;
 
               update_window (w, 1);
-              w->must_be_updated_p = 0;
+              w->must_be_updated_p = false;
 
               /* Swap tool-bar strings.  We swap because we want to
                  reuse strings.  */
@@ -3075,7 +3076,7 @@ update_frame (struct frame *f, bool force_p, bool inhibit_hairy_id_p)
 
  do_pause:
   /* Reset flags indicating that a window should be updated.  */
-  set_window_update_flags (root_window, NULL, 0);
+  set_window_update_flags (root_window, false);
 
   display_completed = !paused_p;
   return paused_p;
@@ -3098,7 +3099,7 @@ update_frame_with_menu (struct frame *f)
      frame matrix we operate.  */
   set_frame_matrix_frame (f);
 
-  /* Update the display  */
+  /* Update the display.  */
   update_begin (f);
   /* Force update_frame_1 not to stop due to pending input, and not
      try scrolling.  */
@@ -3122,7 +3123,7 @@ update_frame_with_menu (struct frame *f)
 #endif
 
   /* Reset flags indicating that a window should be updated.  */
-  set_window_update_flags (root_window, NULL, 0);
+  set_window_update_flags (root_window, false);
 }
 
 
@@ -3174,7 +3175,7 @@ update_single_window (struct window *w, bool force_p)
       update_end (f);
 
       /* Reset flag in W.  */
-      w->must_be_updated_p = 0;
+      w->must_be_updated_p = false;
     }
 }
 
@@ -3897,18 +3898,17 @@ set_window_cursor_after_update (struct window *w)
 }
 
 
-/* If B is NULL, set WINDOW->must_be_updated_p to ON_P for all windows in
-   the window tree rooted at W.  Otherwise set WINDOW->must_be_updated_p
-   to ON_P only for windows that displays B.  */
+/* Set WINDOW->must_be_updated_p to ON_P for all windows in
+   the window tree rooted at W.  */
 
-void
-set_window_update_flags (struct window *w, struct buffer *b, bool on_p)
+static void
+set_window_update_flags (struct window *w, bool on_p)
 {
   while (w)
     {
       if (WINDOWP (w->contents))
-        set_window_update_flags (XWINDOW (w->contents), b, on_p);
-      else if (!(b && b != XBUFFER (w->contents)))
+        set_window_update_flags (XWINDOW (w->contents), on_p);
+      else
         w->must_be_updated_p = on_p;
 
       w = NILP (w->next) ? 0 : XWINDOW (w->next);
diff --git a/src/lisp.h b/src/lisp.h
index 376235a402d..52b20b73ae1 100644
--- a/src/lisp.h
+++ b/src/lisp.h
@@ -3523,7 +3523,7 @@ extern void pop_message_unwind (void);
 extern Lisp_Object restore_message_unwind (Lisp_Object);
 extern void restore_message (void);
 extern Lisp_Object current_message (void);
-extern void clear_message (int, int);
+extern void clear_message (bool, bool);
 extern void message (const char *, ...) ATTRIBUTE_FORMAT_PRINTF (1, 2);
 extern void message1 (const char *);
 extern void message1_nolog (const char *);
diff --git a/src/xdisp.c b/src/xdisp.c
index 0311d5d2d75..28da6bffb92 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -835,7 +835,7 @@ static int single_display_spec_string_p (Lisp_Object, Lisp_Object);
 static int display_prop_string_p (Lisp_Object, Lisp_Object);
 static int row_for_charpos_p (struct glyph_row *, ptrdiff_t);
 static int cursor_row_p (struct glyph_row *);
-static int redisplay_mode_lines (Lisp_Object, int);
+static int redisplay_mode_lines (Lisp_Object, bool);
 static char *decode_mode_spec_coding (Lisp_Object, char *, int);
 
 static Lisp_Object get_it_property (struct it *it, Lisp_Object prop);
@@ -889,7 +889,7 @@ static void sync_frame_with_window_matrix_rows (struct window *);
 static void redisplay_internal (void);
 static int echo_area_display (int);
 static void redisplay_windows (Lisp_Object);
-static void redisplay_window (Lisp_Object, int);
+static void redisplay_window (Lisp_Object, bool);
 static Lisp_Object redisplay_window_error (Lisp_Object);
 static Lisp_Object redisplay_window_0 (Lisp_Object);
 static Lisp_Object redisplay_window_1 (Lisp_Object);
@@ -1429,7 +1429,7 @@ pos_visible_p (struct window *w, ptrdiff_t charpos, int *x, int *y,
       if (top_y < window_top_y)
         visible_p = bottom_y > window_top_y;
       else if (top_y < it.last_visible_y)
-        visible_p = 1;
+        visible_p = true;
       if (bottom_y >= it.last_visible_y
           && it.bidi_p && it.bidi_it.scan_dir == -1
           && IT_CHARPOS (it) < charpos)
@@ -1667,7 +1667,7 @@ pos_visible_p (struct window *w, ptrdiff_t charpos, int *x, int *y,
       if (charpos < IT_CHARPOS (it)
           || (it.what == IT_EOB && charpos == IT_CHARPOS (it)))
         {
-          visible_p = 1;
+          visible_p = true;
           RESTORE_IT (&it2, &it2, it2data);
           move_it_to (&it2, charpos, -1, -1, -1, MOVE_TO_POS);
           *x = it2.current_x;
@@ -2913,7 +2913,7 @@ init_iterator (struct it *it, struct window *w,
          with a left box line.  */
       face = FACE_FROM_ID (it->f, remapped_base_face_id);
       if (face->box != FACE_NO_BOX)
-        it->start_of_box_run_p = 1;
+        it->start_of_box_run_p = true;
     }
 
   /* If a buffer position was specified, set the iterator there,
@@ -3341,7 +3341,7 @@ handle_stop (struct it *it)
                 pop_it (it);
               else
                 {
-                  it->ignore_overlay_strings_at_pos_p = 1;
+                  it->ignore_overlay_strings_at_pos_p = true;
                   it->string_from_display_prop_p = 0;
                   it->from_disp_prop_p = 0;
                   handle_overlay_change_p = 0;
@@ -4206,13 +4206,13 @@ handle_invisible_prop (struct it *it)
                   prop = Fget_text_property (end_charpos, Qinvisible, it->string);
                   invis_p = TEXT_PROP_MEANS_INVISIBLE (prop);
                   if (invis_p == 2)
-                    display_ellipsis_p = 1;
+                    display_ellipsis_p = true;
                 }
             }
           while (invis_p && endpos < len);
 
           if (display_ellipsis_p)
-            it->ellipsis_p = 1;
+            it->ellipsis_p = true;
 
           if (endpos < len)
             {
@@ -4324,9 +4324,9 @@ handle_invisible_prop (struct it *it)
                 tem = next_stop;
 
               /* If there are adjacent invisible texts, don't lose the
-                 second one's ellipsis. */
+                 second one's ellipsis.  */
               if (invis_p == 2)
-                display_ellipsis_p = 1;
+                display_ellipsis_p = true;
             }
           while (invis_p);
 
@@ -4334,10 +4334,10 @@ handle_invisible_prop (struct it *it)
           if (it->bidi_p)
             {
               ptrdiff_t bpos = CHAR_TO_BYTE (newpos);
-              int on_newline =
-                bpos == ZV_BYTE || FETCH_BYTE (bpos) == '\n';
-              int after_newline =
-                newpos <= BEGV || FETCH_BYTE (bpos - 1) == '\n';
+              int on_newline
+                = bpos == ZV_BYTE || FETCH_BYTE (bpos) == '\n';
+              int after_newline
+                = newpos <= BEGV || FETCH_BYTE (bpos - 1) == '\n';
 
               /* If the invisible text ends on a newline or on a
                  character after a newline, we can avoid the costly,
@@ -4444,7 +4444,7 @@ handle_invisible_prop (struct it *it)
                   it->position.charpos = newpos - 1;
                   it->position.bytepos = CHAR_TO_BYTE (it->position.charpos);
                 }
-              it->ellipsis_p = 1;
+              it->ellipsis_p = true;
               /* Let the ellipsis display before
                  considering any properties of the following char.
                  Fixes jasonr@gnu.org 01 Oct 07 bug.  */
@@ -4489,7 +4489,7 @@ setup_for_ellipsis (struct it *it, int len)
     it->saved_face_id = it->face_id = DEFAULT_FACE_ID;
 
   it->method = GET_FROM_DISPLAY_VECTOR;
-  it->ellipsis_p = 1;
+  it->ellipsis_p = true;
 }
 
 
@@ -4958,7 +4958,7 @@ handle_single_display_spec (struct it *it, Lisp_Object spec, Lisp_Object object,
           it->method = GET_FROM_IMAGE;
           it->from_overlay = Qnil;
           it->face_id = face_id;
-          it->from_disp_prop_p = 1;
+          it->from_disp_prop_p = true;
 
           /* Say that we haven't consumed the characters with
              `display' property yet.  The call to pop_it in
@@ -5040,7 +5040,7 @@ handle_single_display_spec (struct it *it, Lisp_Object spec, Lisp_Object object,
          when we are finished with the glyph property value.  */
       push_it (it, position);
       it->from_overlay = overlay;
-      it->from_disp_prop_p = 1;
+      it->from_disp_prop_p = true;
 
       if (NILP (location))
         it->area = TEXT_AREA;
@@ -5060,7 +5060,7 @@ handle_single_display_spec (struct it *it, Lisp_Object spec, Lisp_Object object,
           it->stop_charpos = 0;
           it->prev_stop = 0;
           it->base_level_stop = 0;
-          it->string_from_display_prop_p = 1;
+          it->string_from_display_prop_p = true;
           /* Say that we haven't consumed the characters with
              `display' property yet.  The call to pop_it in
              set_iterator_to_next will clean this up.  */
@@ -5426,7 +5426,7 @@ next_overlay_string (struct it *it)
          processed the overlay strings there already, so that
          next_element_from_buffer doesn't try it again.  */
       if (NILP (it->string) && IT_CHARPOS (*it) >= it->end_charpos)
-        it->overlay_strings_at_end_processed_p = 1;
+        it->overlay_strings_at_end_processed_p = true;
     }
   else
     {
@@ -6109,7 +6109,7 @@ forward_to_next_line_start (struct it *it, int *skipped_p,
               if (bidi_it_prev)
                 *bidi_it_prev = bprev;
             }
-          *skipped_p = newline_found_p = 1;
+          *skipped_p = newline_found_p = true;
         }
       else
         {
@@ -6799,9 +6799,9 @@ get_next_display_element (struct it *it)
           if (! ASCII_CHAR_P (c) && ! NILP (Vnobreak_char_display))
             {
               if (c == 0xA0)
-                nonascii_space_p = 1;
+                nonascii_space_p = true;
               else if (c == 0xAD || c == 0x2010 || c == 0x2011)
-                nonascii_hyphen_p = 1;
+                nonascii_hyphen_p = true;
             }
 
           /* Translate control characters into `\003' or `^C' form.
@@ -7260,12 +7260,12 @@ set_iterator_to_next (struct it *it, int reseat_p)
               if (it->method == GET_FROM_STRING
                   && it->current.overlay_string_index >= 0
                   && it->n_overlay_strings > 0)
-                it->ignore_overlay_strings_at_pos_p = 1;
+                it->ignore_overlay_strings_at_pos_p = true;
               it->len = it->dpvec_char_len;
               set_iterator_to_next (it, reseat_p);
             }
 
-          /* Maybe recheck faces after display vector */
+          /* Maybe recheck faces after display vector.  */
           if (recheck_faces)
             it->stop_charpos = IT_CHARPOS (*it);
         }
@@ -7290,7 +7290,7 @@ set_iterator_to_next (struct it *it, int reseat_p)
       else
         {
           /* Not an overlay string.  There could be padding, so test
-             against it->end_charpos . */
+             against it->end_charpos.  */
           if (IT_STRING_CHARPOS (*it) >= it->end_charpos)
             goto consider_string_end;
         }
@@ -7802,7 +7802,7 @@ next_element_from_string (struct it *it)
 static int
 next_element_from_c_string (struct it *it)
 {
-  int success_p = 1;
+  bool success_p = true;
 
   eassert (it->s);
   eassert (!it->bidi_p || it->s == it->bidi_it.string.s);
@@ -7861,7 +7861,7 @@ next_element_from_ellipsis (struct it *it)
       it->method = GET_FROM_BUFFER;
       it->object = it->w->contents;
       reseat_at_next_visible_line_start (it, 1);
-      it->face_before_selective_p = 1;
+      it->face_before_selective_p = true;
     }
 
   return GET_NEXT_DISPLAY_ELEMENT (it);
@@ -7930,7 +7930,7 @@ compute_stop_pos_backwards (struct it *it)
     it->prev_stop = it->stop_charpos;
   else
     it->prev_stop = BEGV;
-  it->bidi_p = 1;
+  it->bidi_p = true;
   it->current = save_current;
   it->position = save_position;
   it->stop_charpos = save_stop_pos;
@@ -7976,7 +7976,7 @@ handle_stop_backwards (struct it *it, ptrdiff_t charpos)
     }
   while (charpos <= where_we_are);
 
-  it->bidi_p = 1;
+  it->bidi_p = true;
   it->current = save_current;
   it->position = save_position;
   next_stop = it->stop_charpos;
@@ -7993,7 +7993,7 @@ handle_stop_backwards (struct it *it, ptrdiff_t charpos)
 static int
 next_element_from_buffer (struct it *it)
 {
-  int success_p = 1;
+  bool success_p = true;
 
   eassert (IT_CHARPOS (*it) >= BEGV);
   eassert (NILP (it->string) && !it->s);
@@ -8023,7 +8023,7 @@ next_element_from_buffer (struct it *it)
             overlay_strings_follow_p = 0;
           else
             {
-              it->overlay_strings_at_end_processed_p = 1;
+              it->overlay_strings_at_end_processed_p = true;
               overlay_strings_follow_p = get_overlay_strings (it, 0);
             }
 
@@ -9746,7 +9746,7 @@ message3 (Lisp_Object m)
   struct gcpro gcpro1;
 
   GCPRO1 (m);
-  clear_message (1,1);
+  clear_message (true, true);
   cancel_echoing ();
 
   /* First flush out any partial line written with print.  */
@@ -9816,7 +9816,7 @@ message3_nolog (Lisp_Object m)
           echo_message_buffer = Qnil;
         }
       else
-        clear_message (1, 1);
+        clear_message (true, true);
 
       do_pending_window_change (0);
       echo_area_display (1);
@@ -10089,7 +10089,7 @@ with_echo_area_buffer (struct window *w, int which,
   else
     {
       this_one = 0, the_other = 1;
-      clear_buffer_p = 1;
+      clear_buffer_p = true;
 
       /* We need a fresh one in case the current echo buffer equals
          the one containing the last displayed echo area message.  */
@@ -10106,7 +10106,7 @@ with_echo_area_buffer (struct window *w, int which,
         = (EQ (echo_area_buffer[the_other], echo_buffer[this_one])
            ? echo_buffer[the_other]
            : echo_buffer[this_one]);
-      clear_buffer_p = 1;
+      clear_buffer_p = true;
     }
 
   buffer = echo_area_buffer[this_one];
@@ -10732,12 +10732,12 @@ set_message_1 (ptrdiff_t a1, Lisp_Object string)
    last displayed.  */
 
 void
-clear_message (int current_p, int last_displayed_p)
+clear_message (bool current_p, bool last_displayed_p)
 {
   if (current_p)
     {
       echo_area_buffer[0] = Qnil;
-      message_cleared_p = 1;
+      message_cleared_p = true;
     }
 
   if (last_displayed_p)
@@ -10819,7 +10819,7 @@ echo_area_display (int update_frame_p)
     {
       echo_area_window = mini_window;
       window_height_changed_p = display_echo_area (w);
-      w->must_be_updated_p = 1;
+      w->must_be_updated_p = true;
 
       /* Update the display, unless called from redisplay_internal.
          Also don't update the screen during redisplay itself.  The
@@ -10835,7 +10835,7 @@ echo_area_display (int update_frame_p)
              been called, so that mode lines above the echo area are
              garbaged.  This looks odd, so we prevent it here.  */
           if (!display_completed)
-            n = redisplay_mode_lines (FRAME_ROOT_WINDOW (f), 0);
+            n = redisplay_mode_lines (FRAME_ROOT_WINDOW (f), false);
 
           if (window_height_changed_p
               /* Don't do this if Emacs is shutting down.  Redisplay
@@ -12453,7 +12453,7 @@ hscroll_window_tree (Lisp_Object window)
               /* For left-to-right rows, hscroll when cursor is either
                  (i) inside the right hscroll margin, or (ii) if it is
                  inside the left margin and the window is already
-                 hscrolled. */
+                 hscrolled.  */
               && ((!row_r2l_p
                    && ((w->hscroll
                         && w->cursor.x <= h_margin)
@@ -12470,7 +12470,7 @@ hscroll_window_tree (Lisp_Object window)
                       && ((cursor_row->enabled_p
                            /* FIXME: It is confusing to set the
                               truncated_on_right_p flag when R2L rows
-                              are actually truncated on the left. */
+                              are actually truncated on the left.  */
                            && cursor_row->truncated_on_right_p
                            && w->cursor.x <= h_margin)
                           || (w->hscroll
@@ -13425,6 +13425,10 @@ redisplay_internal (void)
 
               if (FRAME_VISIBLE_P (f) && !FRAME_OBSCURED_P (f))
                 redisplay_windows (FRAME_ROOT_WINDOW (f));
+              /* Remember that the invisible frames need to be redisplayed next
+                 time they're visible.  */
+              else if (!REDISPLAY_SOME_P ())
+                f->redisplay = true;
 
               /* The X error handler may have deleted that frame.  */
               if (!FRAME_LIVE_P (f))
@@ -13455,19 +13459,11 @@ redisplay_internal (void)
 
                   /* Prevent various kinds of signals during display
                      update.  stdio is not robust about handling
-                     signals, which can cause an apparent I/O
-                     error.  */
+                     signals, which can cause an apparent I/O error.  */
                   if (interrupt_input)
                     unrequest_sigio ();
                   STOP_POLLING;
 
-                  /* Mark windows on frame F to update.  If we decide to
-                     update all frames but windows_or_buffers_changed is
-                     zero, we assume that only the windows that shows
-                     current buffer should be really updated.  */
-                  set_window_update_flags
-                    (XWINDOW (f->root_window),
-                     (windows_or_buffers_changed ? NULL : current_buffer), 1);
                   pending |= update_frame (f, 0, 0);
                   f->cursor_type_changed = 0;
                   f->updated_p = 1;
@@ -13530,7 +13526,7 @@ redisplay_internal (void)
           if (hscroll_windows (selected_window))
             goto retry;
 
-          XWINDOW (selected_window)->must_be_updated_p = 1;
+          XWINDOW (selected_window)->must_be_updated_p = true;
           pending = update_frame (sf, 0, 0);
           sf->cursor_type_changed = 0;
         }
@@ -13545,7 +13541,7 @@ redisplay_internal (void)
 
       if (mini_frame != sf && FRAME_WINDOW_P (mini_frame))
         {
-          XWINDOW (mini_window)->must_be_updated_p = 1;
+          XWINDOW (mini_window)->must_be_updated_p = true;
           pending |= update_frame (mini_frame, 0, 0);
           mini_frame->cursor_type_changed = 0;
           if (!pending && hscroll_windows (mini_window))
@@ -13846,7 +13842,7 @@ static Lisp_Object
 redisplay_window_0 (Lisp_Object window)
 {
   if (displayed_buffer->display_error_modiff < BUF_MODIFF (displayed_buffer))
-    redisplay_window (window, 0);
+    redisplay_window (window, false);
   return Qnil;
 }
 
@@ -13854,7 +13850,7 @@ static Lisp_Object
 redisplay_window_1 (Lisp_Object window)
 {
   if (displayed_buffer->display_error_modiff < BUF_MODIFF (displayed_buffer))
-    redisplay_window (window, 1);
+    redisplay_window (window, true);
   return Qnil;
 }
 
@@ -15380,7 +15376,7 @@ set_vertical_scroll_bar (struct window *w)
    changed on window's frame.  In that case, redisplay_internal will retry.  */
 
 static void
-redisplay_window (Lisp_Object window, int just_this_one_p)
+redisplay_window (Lisp_Object window, bool just_this_one_p)
 {
   struct window *w = XWINDOW (window);
   struct frame *f = XFRAME (w->frame);
@@ -15391,11 +15387,11 @@ redisplay_window (Lisp_Object window, int just_this_one_p)
   int tem;
   struct it it;
   /* Record it now because it's overwritten.  */
-  int current_matrix_up_to_date_p = 0;
-  int used_current_matrix_p = 0;
+  bool current_matrix_up_to_date_p = false;
+  bool used_current_matrix_p = false;
   /* This is less strict than current_matrix_up_to_date_p.
      It indicates that the buffer contents and narrowing are unchanged.  */
-  int buffer_unchanged_p = 0;
+  bool buffer_unchanged_p = false;
   int temp_scroll_step = 0;
   ptrdiff_t count = SPECPDL_INDEX ();
   int rc;
@@ -15432,6 +15428,11 @@ redisplay_window (Lisp_Object window, int just_this_one_p)
                       || buffer->clip_changed
                       || buffer->prevent_redisplay_optimizations_p);
 
+  if (!just_this_one_p)
+    /* If `just_this_one_p' is set, we apparently set must_be_updated_p more
+       cleverly elsewhere.  */
+    w->must_be_updated_p = true;
+
   if (MINI_WINDOW_P (w))
     {
       if (w == XWINDOW (echo_area_window)
@@ -15512,10 +15513,10 @@ redisplay_window (Lisp_Object window, int just_this_one_p)
       if (XMARKER (w->start)->buffer == current_buffer)
         compute_window_start_on_continuation_line (w);
 
-      w->window_end_valid = 0;
+      w->window_end_valid = false;
       /* If so, we also can't rely on current matrix
          and should not fool try_cursor_movement below.  */
-      current_matrix_up_to_date_p = 0;
+      current_matrix_up_to_date_p = false;
     }
 
   /* Some sanity checks.  */
@@ -16133,7 +16134,7 @@ redisplay_window (Lisp_Object window, int just_this_one_p)
 
   SET_TEXT_POS_FROM_MARKER (startp, w->start);
   w->start_at_line_beg = (CHARPOS (startp) == BEGV
-                            || FETCH_BYTE (BYTEPOS (startp) - 1) == '\n');
+                          || FETCH_BYTE (BYTEPOS (startp) - 1) == '\n');
 
   /* Display the mode line, if we must.  */
   if ((update_mode_line
@@ -16153,6 +16154,7 @@ redisplay_window (Lisp_Object window, int just_this_one_p)
       && (WINDOW_WANTS_MODELINE_P (w)
           || WINDOW_WANTS_HEADER_LINE_P (w)))
     {
+
       display_mode_lines (w);
 
       /* If mode line height has changed, arrange for a thorough
@@ -16273,7 +16275,7 @@ redisplay_window (Lisp_Object window, int just_this_one_p)
 
   set_buffer_internal_1 (old);
   /* Avoid an abort in TEMP_SET_PT_BOTH if the buffer has become
-     shorter.  This can be caused by log truncation in *Messages*. */
+     shorter.  This can be caused by log truncation in *Messages*.  */
   if (CHARPOS (lpoint) <= ZV)
     TEMP_SET_PT_BOTH (CHARPOS (lpoint), BYTEPOS (lpoint));
 
@@ -20740,7 +20742,7 @@ display_tty_menu_item (const char *item_text, int width, int face_id,
    the number of windows whose mode lines were redisplayed.  */
 
 static int
-redisplay_mode_lines (Lisp_Object window, int force)
+redisplay_mode_lines (Lisp_Object window, bool force)
 {
   int nwindows = 0;
 
@@ -20774,10 +20776,7 @@ redisplay_mode_lines (Lisp_Object window, int force)
           /* Display mode lines.  */
           clear_glyph_matrix (w->desired_matrix);
           if (display_mode_lines (w))
-            {
-              ++nwindows;
-              w->must_be_updated_p = 1;
-            }
+            ++nwindows;
 
           /* Restore old settings.  */
           set_buffer_internal_1 (old);
@@ -20833,6 +20832,8 @@ display_mode_lines (struct window *w)
   XFRAME (new_frame)->selected_window = old_frame_selected_window;
   selected_frame = old_selected_frame;
   selected_window = old_selected_window;
+  if (n > 0)
+    w->must_be_updated_p = true;
   return n;
 }
 
diff --git a/src/xterm.c b/src/xterm.c
index b4c2b6aabf6..e80212a6adb 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -98,7 +98,7 @@ extern void _XEditResCheckMessages (Widget, XtPointer, XEvent *, Boolean *);
 
 #ifdef USE_TOOLKIT_SCROLL_BARS
 #if defined USE_MOTIF
-#include <Xm/Xm.h>              /* for LESSTIF_VERSION */
+#include <Xm/Xm.h>              /* For LESSTIF_VERSION */
 #include <Xm/ScrollBar.h>
 #else /* !USE_MOTIF i.e. use Xaw */