Diff of the two buildlogs:

--
--- b1/build.log	2025-07-30 11:35:26.293348711 +0000
+++ b2/build.log	2025-07-30 11:39:04.973626678 +0000
@@ -1,6 +1,6 @@
 I: pbuilder: network access will be disabled during build
-I: Current time: Tue Sep  1 05:56:16 -12 2026
-I: pbuilder-time-stamp: 1788285376
+I: Current time: Thu Jul 31 01:35:28 +14 2025
+I: pbuilder-time-stamp: 1753875328
 I: Building the build Environment
 I: extracting base tarball [/var/cache/pbuilder/experimental-reproducible-base.tgz]
 I: copying local configuration
@@ -26,52 +26,84 @@
 dpkg-source: info: applying 04-cherry-pick-TestIoctlFileDedupeRange-fix.patch
 I: Not using root during the build.
 I: Installing the build-deps
-I: user script /srv/workspace/pbuilder/658915/tmp/hooks/D02_print_environment starting
+I: user script /srv/workspace/pbuilder/1606652/tmp/hooks/D01_modify_environment starting
+debug: Running on ionos1-amd64.
+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 Jul 30 11:35 /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/1606652/tmp/hooks/D01_modify_environment finished
+I: user script /srv/workspace/pbuilder/1606652/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='amd64'
-  DEBIAN_FRONTEND='noninteractive'
-  DEB_BUILD_OPTIONS='buildinfo=+all reproducible=+all parallel=42 '
-  DISTRIBUTION='experimental'
-  HOME='/root'
-  HOST_ARCH='amd64'
+  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]="37" [3]="1" [4]="release" [5]="x86_64-pc-linux-gnu")
+  BASH_VERSION='5.2.37(1)-release'
+  BUILDDIR=/build/reproducible-path
+  BUILDUSERGECOS='second user,second room,second work-phone,second home-phone,second other'
+  BUILDUSERNAME=pbuilder2
+  BUILD_ARCH=amd64
+  DEBIAN_FRONTEND=noninteractive
+  DEB_BUILD_OPTIONS='buildinfo=+all reproducible=+all parallel=40 '
+  DIRSTACK=()
+  DISTRIBUTION=experimental
+  EUID=0
+  FUNCNAME=([0]="Echo" [1]="main")
+  GROUPS=()
+  HOME=/root
+  HOSTNAME=i-capture-the-hostname
+  HOSTTYPE=x86_64
+  HOST_ARCH=amd64
   IFS=' 	
   '
-  INVOCATION_ID='b26382faf1a44b6e8949c70f2b64a576'
-  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='658915'
-  PS1='# '
-  PS2='> '
+  INVOCATION_ID=f113ba8980764ed088f03c2fae41430a
+  LANG=C
+  LANGUAGE=et_EE:et
+  LC_ALL=C
+  MACHTYPE=x86_64-pc-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=1606652
   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.MuBUB3MS/pbuilderrc_3w1z --distribution experimental --hookdir /etc/pbuilder/first-build-hooks --debbuildopts -b --basetgz /var/cache/pbuilder/experimental-reproducible-base.tgz --buildresult /srv/reproducible-results/rbuild-debian/r-b-build.MuBUB3MS/b1 --logfile b1/build.log golang-golang-x-sys_0.22.0-2~exp1.dsc'
-  SUDO_GID='111'
-  SUDO_UID='106'
-  SUDO_USER='jenkins'
-  TERM='unknown'
-  TZ='/usr/share/zoneinfo/Etc/GMT+12'
-  USER='root'
-  _='/usr/bin/systemd-run'
-  http_proxy='http://213.165.73.152:3128'
+  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.MuBUB3MS/pbuilderrc_msqO --distribution experimental --hookdir /etc/pbuilder/rebuild-hooks --debbuildopts -b --basetgz /var/cache/pbuilder/experimental-reproducible-base.tgz --buildresult /srv/reproducible-results/rbuild-debian/r-b-build.MuBUB3MS/b2 --logfile b2/build.log golang-golang-x-sys_0.22.0-2~exp1.dsc'
+  SUDO_GID=110
+  SUDO_UID=105
+  SUDO_USER=jenkins
+  TERM=unknown
+  TZ=/usr/share/zoneinfo/Etc/GMT-14
+  UID=0
+  USER=root
+  _='I: set'
+  http_proxy=http://46.16.76.132:3128
 I: uname -a
-  Linux ionos15-amd64 6.12.33+deb12-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.12.33-1~bpo12+1 (2025-07-09) x86_64 GNU/Linux
+  Linux i-capture-the-hostname 6.1.0-37-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.1.140-1 (2025-05-22) x86_64 GNU/Linux
 I: ls -l /bin
-  lrwxrwxrwx 1 root root 7 May 12  2025 /bin -> usr/bin
-I: user script /srv/workspace/pbuilder/658915/tmp/hooks/D02_print_environment finished
+  lrwxrwxrwx 1 root root 7 May 12 19:25 /bin -> usr/bin
+I: user script /srv/workspace/pbuilder/1606652/tmp/hooks/D02_print_environment finished
  -> Attempting to satisfy build-dependencies
  -> Creating pbuilder-satisfydepends-dummy package
 Package: pbuilder-satisfydepends-dummy
@@ -146,7 +178,7 @@
 Get: 33 http://deb.debian.org/debian unstable/main amd64 golang-src all 2:1.24~2 [5136 B]
 Get: 34 http://deb.debian.org/debian unstable/main amd64 golang-go amd64 2:1.24~2 [44.3 kB]
 Get: 35 http://deb.debian.org/debian unstable/main amd64 golang-any amd64 2:1.24~2 [5216 B]
-Fetched 61.2 MB in 2s (33.7 MB/s)
+Fetched 61.2 MB in 6s (11.1 MB/s)
 Preconfiguring packages ...
 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 ... 19849 files and directories currently installed.)
@@ -301,7 +333,11 @@
 Building tag database...
  -> Finished parsing the build-deps
 I: Building the package
-I: Running cd /build/reproducible-path/golang-golang-x-sys-0.22.0/ && 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-golang-x-sys_0.22.0-2~exp1_source.changes
+I: user script /srv/workspace/pbuilder/1606652/tmp/hooks/A99_set_merged_usr starting
+Not re-configuring usrmerge for experimental
+I: user script /srv/workspace/pbuilder/1606652/tmp/hooks/A99_set_merged_usr finished
+hostname: Name or service not known
+I: Running cd /build/reproducible-path/golang-golang-x-sys-0.22.0/ && 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-golang-x-sys_0.22.0-2~exp1_source.changes
 dpkg-buildpackage: info: source package golang-golang-x-sys
 dpkg-buildpackage: info: source version 0.22.0-2~exp1
 dpkg-buildpackage: info: source distribution experimental
@@ -319,77 +355,77 @@
    dh_autoreconf -O--builddirectory=_build -O--buildsystem=golang
    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 42 golang.org/x/sys/cpu golang.org/x/sys/execabs golang.org/x/sys/unix
-unicode/utf8
-internal/byteorder
-internal/godebugs
-internal/asan
+	cd _build && go install -trimpath -v -p 40 golang.org/x/sys/cpu golang.org/x/sys/execabs golang.org/x/sys/unix
 internal/unsafeheader
-internal/goarch
 internal/goos
-internal/profilerecord
-internal/coverage/rtcov
 internal/msan
-internal/itoa
-internal/goexperiment
-math/bits
 cmp
-sync/atomic
+unicode/utf8
+internal/goarch
+internal/godebugs
+unicode
+internal/coverage/rtcov
+math/bits
 internal/cpu
+internal/byteorder
+sync/atomic
+internal/itoa
 internal/runtime/atomic
-unicode
-internal/runtime/syscall
+internal/abi
 internal/runtime/math
+internal/profilerecord
+internal/runtime/syscall
+internal/goexperiment
+internal/asan
+internal/runtime/sys
 internal/chacha8rand
-internal/abi
 internal/bytealg
 internal/runtime/exithook
-internal/runtime/sys
 math
 internal/stringslite
 internal/race
-internal/sync
 internal/runtime/maps
+internal/sync
 runtime
 internal/reflectlite
-iter
 sync
+iter
 slices
-errors
-sort
 internal/bisect
 internal/testlog
+errors
+sort
+internal/godebug
 internal/oserror
 io
 path
 strconv
 syscall
-internal/godebug
-bytes
 strings
+bytes
 reflect
-internal/syscall/execenv
 internal/syscall/unix
+internal/syscall/execenv
 time
-context
 io/fs
 internal/poll
+context
 internal/filepathlite
 os
 internal/fmtsort
 encoding/binary
 golang.org/x/sys/unix
-golang.org/x/sys/cpu
-path/filepath
 fmt
+path/filepath
+golang.org/x/sys/cpu
 os/exec
 golang.org/x/sys/execabs
    dh_auto_test -O--builddirectory=_build -O--buildsystem=golang
-	cd _build && go test -vet=off -v -p 42 golang.org/x/sys/cpu golang.org/x/sys/execabs golang.org/x/sys/unix
+	cd _build && go test -vet=off -v -p 40 golang.org/x/sys/cpu golang.org/x/sys/execabs golang.org/x/sys/unix
 === RUN   TestParseRelease
 --- PASS: TestParseRelease (0.00s)
 === RUN   TestAuxvFromRuntime
-    runtime_auxv_go121_test.go:16: got: [33 140223824039936 51 1776 16 395049983 6 4096 17 100 3 4194368 4 56 5 6 7 0 8 0 9 4694048 11 1111 12 1111 13 1111 14 1111 23 0 25 140722362123529 26 2 31 140722362130386 15 140722362123545 27 28 28 32]
+    runtime_auxv_go121_test.go:16: got: [33 140736080941056 51 1776 16 395049983 6 4096 17 100 3 4194368 4 56 5 6 7 0 8 0 9 4694048 11 2222 12 2222 13 2222 14 2222 23 0 25 140736080914409 26 2 31 140736080920531 15 140736080914425]
 --- PASS: TestAuxvFromRuntime (0.00s)
 === RUN   TestAMD64minimalFeatures
 --- PASS: TestAMD64minimalFeatures (0.00s)
@@ -406,7 +442,7 @@
 === RUN   TestIsBigEndian
 --- PASS: TestIsBigEndian (0.00s)
 PASS
-ok  	golang.org/x/sys/cpu	0.004s
+ok  	golang.org/x/sys/cpu	0.048s
 === RUN   TestFixCmd
 --- PASS: TestFixCmd (0.00s)
 === RUN   TestCommand
@@ -416,7 +452,7 @@
 === RUN   TestDoesNotExist
 --- PASS: TestDoesNotExist (0.00s)
 PASS
-ok  	golang.org/x/sys/execabs	0.005s
+ok  	golang.org/x/sys/execabs	0.049s
 === RUN   TestNewIfreq
 --- PASS: TestNewIfreq (0.00s)
 === RUN   TestIfreqSize
@@ -558,12 +594,12 @@
     --- PASS: TestDevices//dev/urandom_1:9 (0.00s)
     --- PASS: TestDevices//dev/tty_5:0 (0.00s)
 === RUN   TestDirent
-    dirent_test.go:31: tmpdir: /tmp/TestDirent2614815645/001
+    dirent_test.go:31: tmpdir: /tmp/TestDirent2283282906/001
     dirent_test.go:62: ReadDirent: read 432 bytes
     dirent_test.go:69: ParseDirent: 10 new name(s)
     dirent_test.go:62: ReadDirent: read 0 bytes
     dirent_test.go:76: names: ["00000000000" "111111111111" "2222222222222" "33333333333333" "444444444444444" "5555555555555555" "66666666666666666" "777777777777777777" "8888888888888888888" "99999999999999999999"]
---- PASS: TestDirent (0.00s)
+--- PASS: TestDirent (0.12s)
 === RUN   TestDirentRepeat
 --- PASS: TestDirentRepeat (0.01s)
 === RUN   TestDup3
@@ -600,7 +636,7 @@
 === RUN   TestIoctlIfreq
 --- PASS: TestIoctlIfreq (0.00s)
 === RUN   TestPidfd
---- PASS: TestPidfd (0.00s)
+--- PASS: TestPidfd (0.02s)
 === RUN   TestPpoll
 --- PASS: TestPpoll (0.10s)
 === RUN   TestTime
@@ -610,7 +646,7 @@
 === RUN   TestRlimitAs
 --- PASS: TestRlimitAs (0.00s)
 === RUN   TestPselect
---- PASS: TestPselect (0.00s)
+--- PASS: TestPselect (0.01s)
 === RUN   TestPselectWithSigmask
 --- PASS: TestPselectWithSigmask (0.00s)
 === RUN   TestSchedSetaffinity
@@ -624,7 +660,7 @@
 === RUN   TestClockNanosleep
 --- PASS: TestClockNanosleep (0.10s)
 === RUN   TestOpenByHandleAt
-    syscall_linux_test.go:796: mountID: 96, handle: size=8, type=1, bytes="\xc8\x0f8\x004\xb0\xd9U"
+    syscall_linux_test.go:796: mountID: 94, handle: size=8, type=1, bytes="\x91\x0f\x16\x000\x94\xbd\xd7"
     syscall_linux_test.go:801: openMountByID: mountID not found
 --- SKIP: TestOpenByHandleAt (0.00s)
 === RUN   TestEpoll
@@ -641,13 +677,13 @@
 === RUN   TestPwritevOffsets
 --- PASS: TestPwritevOffsets (0.00s)
 === RUN   TestReadvAllocate
---- PASS: TestReadvAllocate (0.00s)
+--- PASS: TestReadvAllocate (0.03s)
 === RUN   TestSockaddrALG
---- PASS: TestSockaddrALG (0.00s)
+--- PASS: TestSockaddrALG (0.06s)
 === RUN   TestEnv
 --- PASS: TestEnv (0.00s)
 === RUN   TestUname
-    syscall_test.go:42: OS: Linux/x86_64 6.12.33+deb12-amd64
+    syscall_test.go:42: OS: Linux/x86_64 6.1.0-37-amd64
 --- PASS: TestUname (0.00s)
 === RUN   TestStatFieldNames
 --- PASS: TestStatFieldNames (0.00s)
@@ -680,7 +716,7 @@
 === RUN   TestFcntlFlock
 --- PASS: TestFcntlFlock (0.00s)
 === RUN   TestPassFD
---- PASS: TestPassFD (0.00s)
+--- PASS: TestPassFD (0.05s)
 === RUN   TestUnixRightsRoundtrip
 --- PASS: TestUnixRightsRoundtrip (0.00s)
 === RUN   TestRlimit
@@ -721,13 +757,13 @@
 === RUN   TestTimeToTimespec
 --- PASS: TestTimeToTimespec (0.00s)
 === RUN   TestXattr
---- PASS: TestXattr (0.00s)
+--- PASS: TestXattr (0.01s)
 === RUN   TestFdXattr
 --- PASS: TestFdXattr (0.00s)
 === CONT  TestFcntlInt
 --- PASS: TestFcntlInt (0.00s)
 PASS
-ok  	golang.org/x/sys/unix	0.591s
+ok  	golang.org/x/sys/unix	1.178s
    create-stamp debian/debhelper-build-stamp
    dh_testroot -O--builddirectory=_build -O--buildsystem=golang
    dh_prep -O--builddirectory=_build -O--buildsystem=golang
@@ -754,12 +790,14 @@
 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/1606652/tmp/hooks/B01_cleanup starting
+I: user script /srv/workspace/pbuilder/1606652/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/658915 and its subdirectories
-I: Current time: Tue Sep  1 05:58:25 -12 2026
-I: pbuilder-time-stamp: 1788285505
+I: removing directory /srv/workspace/pbuilder/1606652 and its subdirectories
+I: Current time: Thu Jul 31 01:39:04 +14 2025
+I: pbuilder-time-stamp: 1753875544