Diff of the two buildlogs:

--
--- b1/build.log	2024-01-07 23:43:25.112548304 +0000
+++ b2/build.log	2024-01-07 23:44:09.254711116 +0000
@@ -1,7 +1,6 @@
-W: cgroups are not available on the host, not using them.
 I: pbuilder: network access will be disabled during build
-I: Current time: Sun Jan  7 11:42:44 -12 2024
-I: pbuilder-time-stamp: 1704670964
+I: Current time: Mon Jan  8 13:43:27 +14 2024
+I: pbuilder-time-stamp: 1704671007
 I: Building the build Environment
 I: extracting base tarball [/var/cache/pbuilder/bookworm-reproducible-base.tgz]
 I: copying local configuration
@@ -26,48 +25,81 @@
 dpkg-source: info: unpacking golang-uber-automaxprocs_1.4.0-3.debian.tar.xz
 I: Not using root during the build.
 I: Installing the build-deps
-I: user script /srv/workspace/pbuilder/2614395/tmp/hooks/D02_print_environment starting
+I: user script /srv/workspace/pbuilder/2043190/tmp/hooks/D01_modify_environment starting
+debug: Running on codethink04-arm64.
+I: Changing host+domainname to test build reproducibility
+I: Adding a custom variable just for the fun of it...
+I: Changing /bin/sh to bash
+'/bin/sh' -> '/bin/bash'
+lrwxrwxrwx 1 root root 9 Jan  7 23:43 /bin/sh -> /bin/bash
+I: Setting pbuilder2's login shell to /bin/bash
+I: Setting pbuilder2's GECOS to second user,second room,second work-phone,second home-phone,second other
+I: user script /srv/workspace/pbuilder/2043190/tmp/hooks/D01_modify_environment finished
+I: user script /srv/workspace/pbuilder/2043190/tmp/hooks/D02_print_environment starting
 I: set
-  BUILDDIR='/build/reproducible-path'
-  BUILDUSERGECOS='first user,first room,first work-phone,first home-phone,first other'
-  BUILDUSERNAME='pbuilder1'
-  BUILD_ARCH='arm64'
-  DEBIAN_FRONTEND='noninteractive'
+  BASH=/bin/sh
+  BASHOPTS=checkwinsize:cmdhist:complete_fullquote:extquote:force_fignore:globasciiranges:globskipdots:hostcomplete:interactive_comments:patsub_replacement:progcomp:promptvars:sourcepath
+  BASH_ALIASES=()
+  BASH_ARGC=()
+  BASH_ARGV=()
+  BASH_CMDS=()
+  BASH_LINENO=([0]="12" [1]="0")
+  BASH_LOADABLES_PATH=/usr/local/lib/bash:/usr/lib/bash:/opt/local/lib/bash:/usr/pkg/lib/bash:/opt/pkg/lib/bash:.
+  BASH_SOURCE=([0]="/tmp/hooks/D02_print_environment" [1]="/tmp/hooks/D02_print_environment")
+  BASH_VERSINFO=([0]="5" [1]="2" [2]="15" [3]="1" [4]="release" [5]="aarch64-unknown-linux-gnu")
+  BASH_VERSION='5.2.15(1)-release'
+  BUILDDIR=/build/reproducible-path
+  BUILDUSERGECOS='second user,second room,second work-phone,second home-phone,second other'
+  BUILDUSERNAME=pbuilder2
+  BUILD_ARCH=arm64
+  DEBIAN_FRONTEND=noninteractive
   DEB_BUILD_OPTIONS='buildinfo=+all reproducible=+all parallel=12 '
-  DISTRIBUTION='bookworm'
-  HOME='/root'
-  HOST_ARCH='arm64'
+  DIRSTACK=()
+  DISTRIBUTION=bookworm
+  EUID=0
+  FUNCNAME=([0]="Echo" [1]="main")
+  GROUPS=()
+  HOME=/root
+  HOSTNAME=i-capture-the-hostname
+  HOSTTYPE=aarch64
+  HOST_ARCH=arm64
   IFS=' 	
   '
-  LANG='C'
-  LANGUAGE='en_US:en'
-  LC_ALL='C'
-  MAIL='/var/mail/root'
-  OPTIND='1'
-  PATH='/usr/sbin:/usr/bin:/sbin:/bin:/usr/games'
-  PBCURRENTCOMMANDLINEOPERATION='build'
-  PBUILDER_OPERATION='build'
-  PBUILDER_PKGDATADIR='/usr/share/pbuilder'
-  PBUILDER_PKGLIBDIR='/usr/lib/pbuilder'
-  PBUILDER_SYSCONFDIR='/etc'
-  PPID='2614395'
-  PS1='# '
-  PS2='> '
+  INVOCATION_ID=770cf33acadb435fac9b68319c25f51d
+  LANG=C
+  LANGUAGE=nl_BE:nl
+  LC_ALL=C
+  MACHTYPE=aarch64-unknown-linux-gnu
+  MAIL=/var/mail/root
+  OPTERR=1
+  OPTIND=1
+  OSTYPE=linux-gnu
+  PATH=/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/i/capture/the/path
+  PBCURRENTCOMMANDLINEOPERATION=build
+  PBUILDER_OPERATION=build
+  PBUILDER_PKGDATADIR=/usr/share/pbuilder
+  PBUILDER_PKGLIBDIR=/usr/lib/pbuilder
+  PBUILDER_SYSCONFDIR=/etc
+  PIPESTATUS=([0]="0")
+  POSIXLY_CORRECT=y
+  PPID=2043190
   PS4='+ '
-  PWD='/'
-  SHELL='/bin/bash'
-  SHLVL='2'
-  SUDO_COMMAND='/usr/bin/timeout -k 18.1h 18h /usr/bin/ionice -c 3 /usr/bin/nice /usr/sbin/pbuilder --build --configfile /srv/reproducible-results/rbuild-debian/r-b-build.QQqFFGUA/pbuilderrc_PCzI --distribution bookworm --hookdir /etc/pbuilder/first-build-hooks --debbuildopts -b --basetgz /var/cache/pbuilder/bookworm-reproducible-base.tgz --buildresult /srv/reproducible-results/rbuild-debian/r-b-build.QQqFFGUA/b1 --logfile b1/build.log golang-uber-automaxprocs_1.4.0-3.dsc'
-  SUDO_GID='109'
-  SUDO_UID='104'
-  SUDO_USER='jenkins'
-  TERM='unknown'
-  TZ='/usr/share/zoneinfo/Etc/GMT+12'
-  USER='root'
-  _='/usr/sbin/chroot'
-  http_proxy='http://192.168.101.104:3128'
+  PWD=/
+  SHELL=/bin/bash
+  SHELLOPTS=braceexpand:errexit:hashall:interactive-comments:posix
+  SHLVL=3
+  SUDO_COMMAND='/usr/bin/timeout -k 24.1h 24h /usr/bin/ionice -c 3 /usr/bin/nice -n 11 /usr/bin/unshare --uts -- /usr/sbin/pbuilder --build --configfile /srv/reproducible-results/rbuild-debian/r-b-build.QQqFFGUA/pbuilderrc_hDEU --distribution bookworm --hookdir /etc/pbuilder/rebuild-hooks --debbuildopts -b --basetgz /var/cache/pbuilder/bookworm-reproducible-base.tgz --buildresult /srv/reproducible-results/rbuild-debian/r-b-build.QQqFFGUA/b2 --logfile b2/build.log golang-uber-automaxprocs_1.4.0-3.dsc'
+  SUDO_GID=109
+  SUDO_UID=104
+  SUDO_USER=jenkins
+  TERM=unknown
+  TZ=/usr/share/zoneinfo/Etc/GMT-14
+  UID=0
+  USER=root
+  _='I: set'
+  http_proxy=http://192.168.101.104:3128
 I: uname -a
-  Linux codethink02-arm64 6.1.0-17-cloud-arm64 #1 SMP Debian 6.1.69-1 (2023-12-30) aarch64 GNU/Linux
+  Linux i-capture-the-hostname 6.1.0-17-cloud-arm64 #1 SMP Debian 6.1.69-1 (2023-12-30) aarch64 GNU/Linux
 I: ls -l /bin
   total 7104
   -rwxr-xr-x 1 root root 1346480 Apr 23  2023 bash
@@ -127,7 +159,7 @@
   -rwxr-xr-x 1 root root   68480 Sep 20  2022 rmdir
   -rwxr-xr-x 1 root root   68392 Jul 28 23:46 run-parts
   -rwxr-xr-x 1 root root  134536 Jan  5  2023 sed
-  lrwxrwxrwx 1 root root       4 Jan  5  2023 sh -> dash
+  lrwxrwxrwx 1 root root       9 Jan  7 23:43 sh -> /bin/bash
   -rwxr-xr-x 1 root root   68432 Sep 20  2022 sleep
   -rwxr-xr-x 1 root root  134088 Sep 20  2022 stty
   -rwsr-xr-x 1 root root  133312 Mar 23  2023 su
@@ -153,7 +185,7 @@
   -rwxr-xr-x 1 root root    2206 Apr 10  2022 zless
   -rwxr-xr-x 1 root root    1842 Apr 10  2022 zmore
   -rwxr-xr-x 1 root root    4577 Apr 10  2022 znew
-I: user script /srv/workspace/pbuilder/2614395/tmp/hooks/D02_print_environment finished
+I: user script /srv/workspace/pbuilder/2043190/tmp/hooks/D02_print_environment finished
  -> Attempting to satisfy build-dependencies
  -> Creating pbuilder-satisfydepends-dummy package
 Package: pbuilder-satisfydepends-dummy
@@ -236,7 +268,7 @@
 Get: 39 http://deb.debian.org/debian bookworm/main arm64 golang-github-stretchr-objx-dev all 0.5.0-1 [25.5 kB]
 Get: 40 http://deb.debian.org/debian bookworm/main arm64 golang-gopkg-yaml.v3-dev all 3.0.1-3 [74.3 kB]
 Get: 41 http://deb.debian.org/debian bookworm/main arm64 golang-github-stretchr-testify-dev all 1.8.1-1 [67.9 kB]
-Fetched 93.5 MB in 1s (171 MB/s)
+Fetched 93.5 MB in 0s (239 MB/s)
 debconf: delaying package configuration, since apt-utils is not installed
 Selecting previously unselected package sensible-utils.
 (Reading database ... 
(Reading database ... 5%
(Reading database ... 10%
(Reading database ... 15%
(Reading database ... 20%
(Reading database ... 25%
(Reading database ... 30%
(Reading database ... 35%
(Reading database ... 40%
(Reading database ... 45%
(Reading database ... 50%
(Reading database ... 55%
(Reading database ... 60%
(Reading database ... 65%
(Reading database ... 70%
(Reading database ... 75%
(Reading database ... 80%
(Reading database ... 85%
(Reading database ... 90%
(Reading database ... 95%
(Reading database ... 100%
(Reading database ... 18171 files and directories currently installed.)
@@ -415,7 +447,11 @@
 Building tag database...
  -> Finished parsing the build-deps
 I: Building the package
-I: Running cd /build/reproducible-path/golang-uber-automaxprocs-1.4.0/ && env PATH="/usr/sbin:/usr/bin:/sbin:/bin:/usr/games" HOME="/nonexistent/first-build" dpkg-buildpackage -us -uc -b && env PATH="/usr/sbin:/usr/bin:/sbin:/bin:/usr/games" HOME="/nonexistent/first-build" dpkg-genchanges -S  > ../golang-uber-automaxprocs_1.4.0-3_source.changes
+I: user script /srv/workspace/pbuilder/2043190/tmp/hooks/A99_set_merged_usr starting
+Not re-configuring usrmerge for bookworm
+I: user script /srv/workspace/pbuilder/2043190/tmp/hooks/A99_set_merged_usr finished
+hostname: Name or service not known
+I: Running cd /build/reproducible-path/golang-uber-automaxprocs-1.4.0/ && env PATH="/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/i/capture/the/path" HOME="/nonexistent/second-build" dpkg-buildpackage -us -uc -b && env PATH="/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/i/capture/the/path" HOME="/nonexistent/second-build" dpkg-genchanges -S  > ../golang-uber-automaxprocs_1.4.0-3_source.changes
 dpkg-buildpackage: info: source package golang-uber-automaxprocs
 dpkg-buildpackage: info: source version 1.4.0-3
 dpkg-buildpackage: info: source distribution unstable
@@ -434,21 +470,21 @@
    dh_auto_configure -O--builddirectory=_build -O--buildsystem=golang
    dh_auto_build -O--builddirectory=_build -O--buildsystem=golang
 	cd _build && go install -trimpath -v -p 12 go.uber.org/automaxprocs go.uber.org/automaxprocs/internal/cgroups go.uber.org/automaxprocs/internal/runtime go.uber.org/automaxprocs/maxprocs
-internal/goarch
+internal/itoa
 internal/unsafeheader
-internal/goexperiment
 internal/goos
+math/bits
+internal/goexperiment
+unicode/utf8
 internal/race
 unicode
-unicode/utf8
-internal/itoa
-math/bits
+internal/goarch
 internal/cpu
 runtime/internal/syscall
-runtime/internal/math
-internal/abi
 sync/atomic
+internal/abi
 runtime/internal/sys
+runtime/internal/math
 math
 internal/bytealg
 runtime/internal/atomic
@@ -459,8 +495,8 @@
 errors
 sort
 io
-strconv
 internal/oserror
+strconv
 internal/safefilepath
 path
 syscall
@@ -468,26 +504,26 @@
 strings
 reflect
 bufio
+internal/syscall/execenv
 internal/syscall/unix
 time
-internal/syscall/execenv
 internal/poll
 io/fs
 internal/fmtsort
 os
-fmt
 path/filepath
-log
+fmt
 go.uber.org/automaxprocs/internal/cgroups
+log
 go.uber.org/automaxprocs/internal/runtime
 go.uber.org/automaxprocs/maxprocs
 go.uber.org/automaxprocs
    dh_auto_test -O--builddirectory=_build -O--buildsystem=golang
 	cd _build && go test -vet=off -v -p 12 go.uber.org/automaxprocs go.uber.org/automaxprocs/internal/cgroups go.uber.org/automaxprocs/internal/runtime go.uber.org/automaxprocs/maxprocs
-2024/01/07 23:43:12 maxprocs: Leaving GOMAXPROCS=12: CPU quota undefined
+2024/01/07 23:43:57 maxprocs: Leaving GOMAXPROCS=12: CPU quota undefined
 testing: warning: no tests to run
 PASS
-ok  	go.uber.org/automaxprocs	0.030s [no tests to run]
+ok  	go.uber.org/automaxprocs	0.003s [no tests to run]
 === RUN   TestCGroupParamPath
 --- PASS: TestCGroupParamPath (0.00s)
 === RUN   TestCGroupReadFirstLine
@@ -513,7 +549,7 @@
 === RUN   TestNewCGroupSubsysFromLineErr
 --- PASS: TestNewCGroupSubsysFromLineErr (0.00s)
 PASS
-ok  	go.uber.org/automaxprocs/internal/cgroups	0.045s
+ok  	go.uber.org/automaxprocs/internal/cgroups	0.011s
 ?   	go.uber.org/automaxprocs/internal/runtime	[no test files]
 === RUN   TestLogger
 === RUN   TestLogger/default
@@ -529,16 +565,16 @@
 === RUN   TestSet/QuotaTooSmall
 === RUN   TestSet/Min_unused
 === RUN   TestSet/QuotaUsed
---- PASS: TestSet (0.03s)
+--- PASS: TestSet (0.00s)
     --- PASS: TestSet/EnvVarPresent (0.00s)
     --- PASS: TestSet/ErrorReadingQuota (0.00s)
     --- PASS: TestSet/QuotaUndefined (0.00s)
     --- PASS: TestSet/QuotaUndefined_return_maxProcs=7 (0.00s)
-    --- PASS: TestSet/QuotaTooSmall (0.01s)
-    --- PASS: TestSet/Min_unused (0.01s)
-    --- PASS: TestSet/QuotaUsed (0.01s)
+    --- PASS: TestSet/QuotaTooSmall (0.00s)
+    --- PASS: TestSet/Min_unused (0.00s)
+    --- PASS: TestSet/QuotaUsed (0.00s)
 PASS
-ok  	go.uber.org/automaxprocs/maxprocs	0.054s
+ok  	go.uber.org/automaxprocs/maxprocs	0.010s
    create-stamp debian/debhelper-build-stamp
    dh_testroot -O--builddirectory=_build -O--buildsystem=golang
    dh_prep -O--builddirectory=_build -O--buildsystem=golang
@@ -565,12 +601,14 @@
 dpkg-buildpackage: info: binary-only upload (no source included)
 dpkg-genchanges: info: not including original source code in upload
 I: copying local configuration
+I: user script /srv/workspace/pbuilder/2043190/tmp/hooks/B01_cleanup starting
+I: user script /srv/workspace/pbuilder/2043190/tmp/hooks/B01_cleanup finished
 I: unmounting dev/ptmx filesystem
 I: unmounting dev/pts filesystem
 I: unmounting dev/shm filesystem
 I: unmounting proc filesystem
 I: unmounting sys filesystem
 I: cleaning the build env 
-I: removing directory /srv/workspace/pbuilder/2614395 and its subdirectories
-I: Current time: Sun Jan  7 11:43:23 -12 2024
-I: pbuilder-time-stamp: 1704671003
+I: removing directory /srv/workspace/pbuilder/2043190 and its subdirectories
+I: Current time: Mon Jan  8 13:44:08 +14 2024
+I: pbuilder-time-stamp: 1704671048