Minor optimization to x_query_pointer_1

* src/xterm.c (x_query_pointer_1): Clear client pointer if it
disappeared.

1 files changed, 14 insertions, 4 deletions

diff --git a/src/xterm.c b/src/xterm.c
index 39e5a8e1861..4f9b0b83b55 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -13442,10 +13442,20 @@ x_query_pointer_1 (struct x_display_info *dpyinfo,
       x_uncatch_errors_after_check ();
 
       if (had_errors)
-        rc = XQueryPointer (dpyinfo->display, w, root_return,
-                            child_return, root_x_return,
-                            root_y_return, win_x_return,
-                            win_y_return, mask_return);
+        {
+          /* If the specified client pointer is the display's client
+             pointer, clear it now.  A new client pointer might not be
+             found before the next call to x_query_pointer_1 and
+             waiting for the error leads to excessive syncing.  */
+
+          if (client_pointer_device == dpyinfo->client_pointer_device)
+            dpyinfo->client_pointer_device = -1;
+
+          rc = XQueryPointer (dpyinfo->display, w, root_return,
+                              child_return, root_x_return,
+                              root_y_return, win_x_return,
+                              win_y_return, mask_return);
+        }
       else
         {
           state = 0;