Fix redrawing non-selected frame after resize on MS-Windows

* src/xdisp.c (redisplay_internal): If all the frames were
successfully updated, reset the "garbaged" flag of each frame, to
make sure it doesn't stay set.

* src/w32term.c (w32_read_socket): Don't clear the frame if it's
"garbaged", since expose_frame won't redraw the foreground then.
(Bug#24642)

2 files changed, 12 insertions, 4 deletions

diff --git a/src/w32term.c b/src/w32term.c
index e8d66c9e5a1..ae0f741f24c 100644
--- a/src/w32term.c
+++ b/src/w32term.c
@@ -4628,11 +4628,18 @@ w32_read_socket (struct terminal *terminal,
 		}
 	      else
 		{
-		  HDC hdc = get_frame_dc (f);
+		  /* Erase background again for safety.  But don't do
+		     that if the frame's 'garbaged' flag is set, since
+		     in that case expose_frame will do nothing, and if
+		     the various redisplay flags happen to be unset,
+		     we are left with a blank frame.  */
+		  if (!FRAME_GARBAGED_P (f))
+		    {
+		      HDC hdc = get_frame_dc (f);
 
-		  /* Erase background again for safety.  */
-		  w32_clear_rect (f, hdc, &msg.rect);
-		  release_frame_dc (f, hdc);
+		      w32_clear_rect (f, hdc, &msg.rect);
+		      release_frame_dc (f, hdc);
+		    }
 		  expose_frame (f,
 				msg.rect.left,
 				msg.rect.top,
diff --git a/src/xdisp.c b/src/xdisp.c
index c045ced000b..1420a4a7e36 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -14116,6 +14116,7 @@ redisplay_internal (void)
               if (f->updated_p)
                 {
 		  f->redisplay = false;
+		  f->garbaged = false;
                   mark_window_display_accurate (f->root_window, true);
                   if (FRAME_TERMINAL (f)->frame_up_to_date_hook)
                     FRAME_TERMINAL (f)->frame_up_to_date_hook (f);