NO_ROOT+DESTDIR: Permission denied?

From: Andriy Gapon <avg_at_FreeBSD.org>
Date: Fri, 01 Oct 2021 10:13:33 UTC 
When installing world with NO_ROOT and DESTDIR set I see a handful of permission 
denied errors like below:

--------------------------------------------------------------
 >>> Installing everything started on Fri Oct  1 13:09:32 EEST 2021
--------------------------------------------------------------
make[3]: 
"/usr/obj/apu2c4/usr/devel/git/apu2c4/amd64.amd64/toolchain-metadata.mk" line 1: 
Using cached toolchain metadata from build at trant on Mon 27 Sep 2021 16:29:14 EEST
===> lib (install)
===> bin (install)
===> cddl (install)
===> libexec (install)
===> gnu (install)
make[4] warning: /bin: Permission denied.
===> include (install)
make[4] warning: /lib: Permission denied.
make[4] warning: /libexec: Permission denied.

installworld works despite those and the result looks fine, but the messages a 
re little bit concerning.

Perhaps, DESTDIR is not honored in some place?

The able is for installing CURRENT on a stable/13 host.
-- 
Andriy Gapon