diff --git a/sys/sys/umtxvar.h b/sys/sys/umtxvar.h
--- a/sys/sys/umtxvar.h
+++ b/sys/sys/umtxvar.h
@@ -51,6 +51,7 @@
 	TYPE_SHM,
 	TYPE_PI_ROBUST_UMUTEX,
 	TYPE_PP_ROBUST_UMUTEX,
+	TYPE_PI_FUTEX,
 };
 
 /* Key to represent a unique userland synchronous object */