--- 15.11/common/lib/modules/fglrx/build_mod/firegl_public.c	2015-11-21 00:35:38.000000000 +0100
+++ 15.11b/common/lib/modules/fglrx/build_mod/firegl_public.c	2015-11-24 22:28:02.113843493 +0100
@@ -1714,6 +1714,9 @@
 
 #if defined(__i386__) 
 #ifndef __HAVE_ARCH_CMPXCHG
+#ifndef __xg
+#define __xg(x) ((volatile long *)(x))
+#endif
 static inline 
 unsigned long __fgl_cmpxchg(volatile void *ptr, unsigned long old,            
                         unsigned long new, int size)