diff --git a/xen/xsm/flask/flask_op.c b/xen/xsm/flask/flask_op.c
index 3b84679406..9dd908169f 100644
--- a/xen/xsm/flask/flask_op.c
+++ b/xen/xsm/flask/flask_op.c
@@ -785,7 +785,7 @@ ret_t do_flask_op(XEN_GUEST_HANDLE_PARAM(xsm_op_t) u_flask_op)
     return rv;
 }
 
-#ifndef COMPAT
+#if defined(CONFIG_COMPAT) && !defined(COMPAT)
 #undef _copy_to_guest
 #define _copy_to_guest copy_to_compat
 #undef _copy_from_guest