diff --git a/xen/common/sched/compat.c b/xen/common/sched/compat.c
index a596e3a226..d718e450d4 100644
--- a/xen/common/sched/compat.c
+++ b/xen/common/sched/compat.c
@@ -3,6 +3,10 @@
  *
  */
 
+#ifndef __COMMON_SCHED_COMPAT_C__
+#define __COMMON_SCHED_COMPAT_C__
+
+
 #include <compat/sched.h>
 
 #define COMPAT
@@ -44,6 +48,8 @@ int compat_set_timer_op(uint32_t lo, int32_t hi)
     return do_set_timer_op(((s64)hi << 32) | lo);
 }
 
+#endif /* __COMMON_SCHED_COMPAT_C__ */
+
 /*
  * Local variables:
  * mode: C