src/java.desktop/unix/classes/sun/awt/X11/XlibWrapper.java

@@ -527,11 +527,11 @@
     /*
       int (*XSynchronize(Display *display, Bool onoff))();
           display   Specifies the connection to the X server.
           onoff     Specifies a Boolean value that indicates whether to enable or disable synchronization.
      */
-    static native int XSynchronize(long display, boolean onoff);
+    static native long XSynchronize(long display, boolean onoff);
 
     /**
      * Extracts an X event that can be processed in a secondary loop.
      * Should only be called on the toolkit thread.
      * Returns false if this secondary event was terminated.