diff --git a/ospf6d/ospf6_route.h b/ospf6d/ospf6_route.h
index 069502f..3d3e101 100644
--- a/ospf6d/ospf6_route.h
+++ b/ospf6d/ospf6_route.h
@@ -215,9 +215,9 @@
 #define ospf6_linkstate_prefix_id(x) \
   (*(u_int32_t *)(&(x)->u.prefix6.s6_addr[4]))
 
-#define ID_IN_PREFIX(x) \
-  (*(u_int32_t *)(&(x)->u.prefix6.s6_addr[0]))
 #define ADV_ROUTER_IN_PREFIX(x) \
+  (*(u_int32_t *)(&(x)->u.prefix6.s6_addr[0]))
+#define ID_IN_PREFIX(x) \
   (*(u_int32_t *)(&(x)->u.prefix6.s6_addr[4]))
 
 /* Function prototype */