[PATCH xserver 1/2] present: Make present_restore_screen_pixmap handle screen->root == NULL

[Michel Dänzer]

From: Michel Dänzer <michel.daenzer at amd.com>

Easier than dealing with it in all paths that can end up here during
server shutdown.

Signed-off-by: Michel Dänzer <michel.daenzer at amd.com>
---
 present/present.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/present/present.c b/present/present.c
index 5fde846..8d37395 100644
--- a/present/present.c
+++ b/present/present.c
@@ -439,7 +439,7 @@ present_restore_screen_pixmap(ScreenPtr screen)
      * Only do this the first time for a particular unflip operation, or
      * we'll probably scribble over other windows
      */
-    if (screen->GetWindowPixmap(screen->root) == flip_pixmap)
+    if (screen->root && screen->GetWindowPixmap(screen->root) == flip_pixmap)
         present_copy_region(&screen_pixmap->drawable, flip_pixmap, NULL, 0, 0);
 
     /* Switch back to using the screen pixmap now to avoid
@@ -447,7 +447,8 @@ present_restore_screen_pixmap(ScreenPtr screen)
      */
     if (flip_window)
         present_set_tree_pixmap(flip_window, flip_pixmap, screen_pixmap);
-    present_set_tree_pixmap(screen->root, NULL, screen_pixmap);
+    if (screen->root)
+        present_set_tree_pixmap(screen->root, NULL, screen_pixmap);
 }
 
 static void
-- 
2.8.1