Fix bug #14616 with unnecessary redrawing of TTY frames.

 src/xdisp.c (prepare_menu_bars): Don't call x_consider_frame_title
 for TTY frames that are not the top frame on their console.

2 files changed, 18 insertions, 1 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index f759584fb79..a0363732164 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,9 @@
+2013-08-07  Eli Zaretskii  <eliz@gnu.org>
+
+        * xdisp.c (prepare_menu_bars): Don't call x_consider_frame_title
+        for TTY frames that are not the top frame on their console.
+        (Bug#14616)
+
 2013-08-07  Martin Rudalics  <rudalics@gmx.at>
 
         * w32term.c (w32fullscreen_hook): Really maximize frame when
diff --git a/src/xdisp.c b/src/xdisp.c
index 5e6311ed98d..fc19b5ce6d7 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -11169,7 +11169,18 @@ prepare_menu_bars (void)
         {
           f = XFRAME (frame);
           if (!EQ (frame, tooltip_frame)
-              && (FRAME_VISIBLE_P (f) || FRAME_ICONIFIED_P (f)))
+              && (FRAME_ICONIFIED_P (f)
+                  || FRAME_VISIBLE_P (f) == 1
+                  /* Exclude TTY frames that are obscured because they
+                     are not the top frame on their console.  This is
+                     because x_consider_frame_title actually swit6ches
+                     to the frame, which for TTY frames means it is
+                     marked as garbaged, and will be completely
+                     redrawn on the next redisplay cycle.  This causes
+                     TTY frames to be completely redrawn, when there
+                     are more than one of them, even though nothing
+                     should be changed on display.  */
+                  || (FRAME_VISIBLE_P (f) == 2 && FRAME_WINDOW_P (f))))
             x_consider_frame_title (frame);
         }
     }