src/java.desktop/unix/native/libawt_xawt/awt/wsutils.h

@@ -1,7 +1,7 @@
 /*
- * Copyright (c) 1999, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2020, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.  Oracle designates this

@@ -68,10 +68,14 @@
  * This file contains various typedef's, macros and procedure declarations for
  * a set of example utility procedures contained in the file "wsutils.c".
  *
  ******************************************************************************/
 
+#ifdef HEADLESS
+    #error This file should not be included in headless library
+#endif
+
 typedef unsigned long Pixel;
 
 /* This is the actual structure returned by the X server describing the
  * SERVER_OVERLAY_VISUAL property.
  */