diff --git a/sys/conf/kern.post.mk b/sys/conf/kern.post.mk
index f38dbf34a913..aa6cc60202ec 100644
--- a/sys/conf/kern.post.mk
+++ b/sys/conf/kern.post.mk
@@ -79,7 +79,7 @@ PORTSMODULESENV=\
 all:
 .for __i in ${PORTS_MODULES}
 	@${ECHO} "===> Ports module ${__i} (all)"
-	cd $${PORTSDIR:-/usr/ports}/${__i}; ${PORTSMODULESENV} ${MAKE} -B clean all
+	cd $${PORTSDIR:-/usr/ports}/${__i}; ${PORTSMODULESENV} ${MAKE} -B clean build
 .endfor
 
 .for __target in install reinstall clean