diff --git a/include/types/backend.h b/include/types/backend.h
index 68d3125..c7f9fa3 100644
--- a/include/types/backend.h
+++ b/include/types/backend.h
@@ -147,9 +147,8 @@
 	struct lb_fwlc fwlc;
 	struct lb_chash chash;
 	struct lb_fas fas;
-#ifdef USE_THREAD
-	HA_SPINLOCK_T lock;
-#endif
+	__decl_hathreads(HA_SPINLOCK_T lock);
+
 	/* Call backs for some actions. Any of them may be NULL (thus should be ignored). */
 	void (*update_server_eweight)(struct server *);  /* to be called after eweight change */
 	void (*set_server_status_up)(struct server *);   /* to be called after status changes to UP */