I did 2 test buildworld's based on:
# ~/fbsd-based-on-what-freebsd.sh
branch: releng/13.0
merge-base: ea31abc261ffc01b6ff5671bffb15cf910a07f4b
merge-base: CommitDate: 2021-04-09 00:14:30 +0000
ea31abc261ff (HEAD -> releng/13.0, tag: release/13.0.0, freebsd/releng/13.0)
13.0: update to RELEASE
n244733 (--first-parent --count for merge-base)
and produced separate build trees. I also installed the
world build into two separate directory trees:
/usr/obj/DESTDIRs/13_0R-CA7-chroot/
vs.
/usr/obj/DESTDIRs/13_0R-CA7-poud/
This was for other reasons. But eventually I happened
to do a diff -rq of the two trees and ended up with
the output showing some differing files:
Files /usr/obj/DESTDIRs/13_0R-CA7-chroot/sbin/ping and
/usr/obj/DESTDIRs/13_0R-CA7-poud/sbin/ping differ
Files /usr/obj/DESTDIRs/13_0R-CA7-chroot/sbin/ping6 and
/usr/obj/DESTDIRs/13_0R-CA7-poud/sbin/ping6 differ
Files /usr/obj/DESTDIRs/13_0R-CA7-chroot/usr/bin/ntpq and
/usr/obj/DESTDIRs/13_0R-CA7-poud/usr/bin/ntpq differ
Files /usr/obj/DESTDIRs/13_0R-CA7-chroot/usr/lib/debug/sbin/ping.debug and
/usr/obj/DESTDIRs/13_0R-CA7-poud/usr/lib/debug/sbin/ping.debug differ
Files /usr/obj/DESTDIRs/13_0R-CA7-chroot/usr/lib/debug/usr/sbin/ntpd.debug and
/usr/obj/DESTDIRs/13_0R-CA7-poud/usr/lib/debug/usr/sbin/ntpd.debug differ
Files
/usr/obj/DESTDIRs/13_0R-CA7-chroot/usr/lib/debug/usr/tests/sbin/ping/in_cksum_test.debug
and
/usr/obj/DESTDIRs/13_0R-CA7-poud/usr/lib/debug/usr/tests/sbin/ping/in_cksum_test.debug
differ
Files /usr/obj/DESTDIRs/13_0R-CA7-chroot/usr/sbin/ntp-keygen and
/usr/obj/DESTDIRs/13_0R-CA7-poud/usr/sbin/ntp-keygen differ
Files /usr/obj/DESTDIRs/13_0R-CA7-chroot/usr/sbin/ntpd and
/usr/obj/DESTDIRs/13_0R-CA7-poud/usr/sbin/ntpd differ
Files /usr/obj/DESTDIRs/13_0R-CA7-chroot/usr/sbin/ntpdate and
/usr/obj/DESTDIRs/13_0R-CA7-poud/usr/sbin/ntpdate differ
Files /usr/obj/DESTDIRs/13_0R-CA7-chroot/usr/sbin/ntpdc and
/usr/obj/DESTDIRs/13_0R-CA7-poud/usr/sbin/ntpdc differ
Files /usr/obj/DESTDIRs/13_0R-CA7-chroot/usr/sbin/sntp and
/usr/obj/DESTDIRs/13_0R-CA7-poud/usr/sbin/sntp differ
Files /usr/obj/DESTDIRs/13_0R-CA7-chroot/usr/tests/sbin/ping/in_cksum_test and
/usr/obj/DESTDIRs/13_0R-CA7-poud/usr/tests/sbin/ping/in_cksum_test differ
(That is all.)
For as much as I've looked at (not much), it looks to be
variations in byte-padding values.
The builds both were set up to tune for cortex-a7 explicitly.
I patch top's source code. I patch the OOM kill code to report
the specific reason for a kill. I still have some bcm2838
pci/xhci patching in place from an old investigation, but
that would be kernel code. None of the patching is specific
to the above list of files.
The hosting context was:
# uname -apKU
FreeBSD CA72_4c8G_ZFS 13.0-RELEASE FreeBSD 13.0-RELEASE #1
releng/13.0-n244733-ea31abc261ff-dirty: Wed Apr 28 05:45:27 PDT 2021 root at
CA72_4c8G_ZFS:/usr/obj/BUILDs/13_0R-CA72-nodbg-clang/usr/src/arm64.aarch64/sys/GENERIC-NODBG-CA72
arm64 aarch64 1300139 1300139
based on building the same source code (tuning for
cortex-a72).
It was the same media for all the activity. Unlike
the past many years for me, the context is using ZFS
instead of UFS, not that I think that makes a
difference here.
The differences do not mess up my activity but others
might notice and care about such differences.
==Mark Millard
marklmi at yahoo.com
( dsl-only.net went
away in early 2018-Mar)