Diff of the two buildlogs:

--
--- b1/build.log	2024-12-16 06:18:13.684714628 +0000
+++ b2/build.log	2024-12-16 06:22:25.841208553 +0000
@@ -1,6 +1,6 @@
 I: pbuilder: network access will be disabled during build
-I: Current time: Sun Dec 15 18:14:39 -12 2024
-I: pbuilder-time-stamp: 1734329679
+I: Current time: Mon Dec 16 20:18:23 +14 2024
+I: pbuilder-time-stamp: 1734329903
 I: Building the build Environment
 I: extracting base tarball [/var/cache/pbuilder/unstable-reproducible-base.tgz]
 I: copying local configuration
@@ -31,52 +31,84 @@
 dpkg-source: info: applying kernel-user_ns-accept-mapping.patch
 I: Not using root during the build.
 I: Installing the build-deps
-I: user script /srv/workspace/pbuilder/19099/tmp/hooks/D02_print_environment starting
+I: user script /srv/workspace/pbuilder/26917/tmp/hooks/D01_modify_environment starting
+debug: Running on ff4a.
+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 Dec 16 06:18 /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/26917/tmp/hooks/D01_modify_environment finished
+I: user script /srv/workspace/pbuilder/26917/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='armhf'
-  DEBIAN_FRONTEND='noninteractive'
-  DEB_BUILD_OPTIONS='buildinfo=+all reproducible=+all parallel=3 '
-  DISTRIBUTION='unstable'
-  HOME='/root'
-  HOST_ARCH='armhf'
+  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]="arm-unknown-linux-gnueabihf")
+  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=armhf
+  DEBIAN_FRONTEND=noninteractive
+  DEB_BUILD_OPTIONS='buildinfo=+all reproducible=+all parallel=4 '
+  DIRSTACK=()
+  DISTRIBUTION=unstable
+  EUID=0
+  FUNCNAME=([0]="Echo" [1]="main")
+  GROUPS=()
+  HOME=/root
+  HOSTNAME=i-capture-the-hostname
+  HOSTTYPE=arm
+  HOST_ARCH=armhf
   IFS=' 	
   '
-  INVOCATION_ID='016278a360a64468a6d6d1c8b9f49f37'
-  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='19099'
-  PS1='# '
-  PS2='> '
+  INVOCATION_ID=8e6df972bbbf4defbe1c7854f0966aee
+  LANG=C
+  LANGUAGE=it_CH:it
+  LC_ALL=C
+  MACHTYPE=arm-unknown-linux-gnueabihf
+  MAIL=/var/mail/root
+  OPTERR=1
+  OPTIND=1
+  OSTYPE=linux-gnueabihf
+  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=26917
   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.SjdGRscN/pbuilderrc_V1wx --distribution unstable --hookdir /etc/pbuilder/first-build-hooks --debbuildopts -b --basetgz /var/cache/pbuilder/unstable-reproducible-base.tgz --buildresult /srv/reproducible-results/rbuild-debian/r-b-build.SjdGRscN/b1 --logfile b1/build.log ipykernel_6.29.5-2.dsc'
-  SUDO_GID='113'
-  SUDO_UID='107'
-  SUDO_USER='jenkins'
-  TERM='unknown'
-  TZ='/usr/share/zoneinfo/Etc/GMT+12'
-  USER='root'
-  _='/usr/bin/systemd-run'
-  http_proxy='http://10.0.0.15:3142/'
+  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.SjdGRscN/pbuilderrc_QCXp --distribution unstable --hookdir /etc/pbuilder/rebuild-hooks --debbuildopts -b --basetgz /var/cache/pbuilder/unstable-reproducible-base.tgz --buildresult /srv/reproducible-results/rbuild-debian/r-b-build.SjdGRscN/b2 --logfile b2/build.log ipykernel_6.29.5-2.dsc'
+  SUDO_GID=113
+  SUDO_UID=107
+  SUDO_USER=jenkins
+  TERM=unknown
+  TZ=/usr/share/zoneinfo/Etc/GMT-14
+  UID=0
+  USER=root
+  _='I: set'
+  http_proxy=http://10.0.0.15:3142/
 I: uname -a
-  Linux virt64c 6.1.0-28-arm64 #1 SMP Debian 6.1.119-1 (2024-11-22) aarch64 GNU/Linux
+  Linux i-capture-the-hostname 6.1.0-28-armmp-lpae #1 SMP Debian 6.1.119-1 (2024-11-22) armv7l GNU/Linux
 I: ls -l /bin
   lrwxrwxrwx 1 root root 7 Nov 22 14:40 /bin -> usr/bin
-I: user script /srv/workspace/pbuilder/19099/tmp/hooks/D02_print_environment finished
+I: user script /srv/workspace/pbuilder/26917/tmp/hooks/D02_print_environment finished
  -> Attempting to satisfy build-dependencies
  -> Creating pbuilder-satisfydepends-dummy package
 Package: pbuilder-satisfydepends-dummy
@@ -313,7 +345,7 @@
 Get: 153 http://deb.debian.org/debian unstable/main armhf python3-sniffio all 1.3.1-1 [7120 B]
 Get: 154 http://deb.debian.org/debian unstable/main armhf python3-sortedcontainers all 2.4.0-2 [31.9 kB]
 Get: 155 http://deb.debian.org/debian unstable/main armhf python3-trio all 0.27.0-1 [317 kB]
-Fetched 54.6 MB in 3s (20.0 MB/s)
+Fetched 54.6 MB in 3s (16.5 MB/s)
 debconf: delaying package configuration, since apt-utils is not installed
 Selecting previously unselected package libproc2-0:armhf.
 (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 ... 19680 files and directories currently installed.)
@@ -821,8 +853,8 @@
 Setting up tzdata (2024b-4) ...
 
 Current default time zone: 'Etc/UTC'
-Local time is now:      Mon Dec 16 06:15:48 UTC 2024.
-Universal Time is now:  Mon Dec 16 06:15:48 UTC 2024.
+Local time is now:      Mon Dec 16 06:19:44 UTC 2024.
+Universal Time is now:  Mon Dec 16 06:19:44 UTC 2024.
 Run 'dpkg-reconfigure tzdata' if you wish to change it.
 
 Setting up libpython3.13-minimal:armhf (3.13.1-2) ...
@@ -971,7 +1003,11 @@
 Building tag database...
  -> Finished parsing the build-deps
 I: Building the package
-I: Running cd /build/reproducible-path/ipykernel-6.29.5/ && 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  > ../ipykernel_6.29.5-2_source.changes
+I: user script /srv/workspace/pbuilder/26917/tmp/hooks/A99_set_merged_usr starting
+Not re-configuring usrmerge for unstable
+I: user script /srv/workspace/pbuilder/26917/tmp/hooks/A99_set_merged_usr finished
+hostname: Name or service not known
+I: Running cd /build/reproducible-path/ipykernel-6.29.5/ && 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  > ../ipykernel_6.29.5-2_source.changes
 dpkg-buildpackage: info: source package ipykernel
 dpkg-buildpackage: info: source version 6.29.5-2
 dpkg-buildpackage: info: source distribution unstable
@@ -1011,11 +1047,11 @@
 rootdir: /build/reproducible-path/ipykernel-6.29.5/.pybuild/cpython3_3.13/build
 configfile: pyproject.toml
 testpaths: tests, tests/inprocess
-plugins: timeout-2.3.1, asyncio-0.24.0a1, typeguard-4.4.1, flaky-3.8.1
+plugins: asyncio-0.24.0a1, flaky-3.8.1, typeguard-4.4.1, timeout-2.3.1
+asyncio: mode=Mode.AUTO, default_loop_scope=None
 timeout: 300.0s
 timeout method: signal
 timeout func_only: False
-asyncio: mode=Mode.AUTO, default_loop_scope=None
 collecting ... collected 12 items
 
 tests/inprocess/test_kernel.py::test_with_cell_id PASSED                 [  8%]
@@ -1047,20 +1083,20 @@
 
 ===End Flaky Test Report===
 ============================= slowest 10 durations =============================
-1.51s call     tests/inprocess/test_kernelmanager.py::InProcessKernelManagerTestCase::test_complete
-0.69s setup    tests/inprocess/test_kernel.py::test_with_cell_id
-0.26s call     tests/inprocess/test_kernelmanager.py::InProcessKernelManagerTestCase::test_history
-0.24s call     tests/inprocess/test_kernelmanager.py::InProcessKernelManagerTestCase::test_inspect
+1.68s call     tests/inprocess/test_kernelmanager.py::InProcessKernelManagerTestCase::test_complete
+0.61s setup    tests/inprocess/test_kernel.py::test_with_cell_id
+0.25s call     tests/inprocess/test_kernelmanager.py::InProcessKernelManagerTestCase::test_history
+0.24s setup    tests/inprocess/test_kernel.py::test_pylab
 0.23s setup    tests/inprocess/test_kernel.py::test_getpass_stream
 0.23s call     tests/inprocess/test_kernelmanager.py::InProcessKernelManagerTestCase::test_execute
-0.22s setup    tests/inprocess/test_kernel.py::test_pylab
+0.22s call     tests/inprocess/test_kernelmanager.py::InProcessKernelManagerTestCase::test_inspect
 0.22s setup    tests/inprocess/test_kernel.py::test_do_execute
-0.22s setup    tests/inprocess/test_kernel.py::test_raw_input
 0.22s setup    tests/inprocess/test_kernel.py::test_stdout
+0.21s setup    tests/inprocess/test_kernel.py::test_raw_input
 =========================== short test summary info ============================
 SKIPPED [1] tests/inprocess/test_kernel.py:58: This test requires matplotlib
 SKIPPED [1] tests/inprocess/test_kernel.py:92: Currently don't capture during test as pytest does its own capturing
-=================== 10 passed, 2 skipped, 1 warning in 4.43s ===================
+=================== 10 passed, 2 skipped, 1 warning in 4.51s ===================
 I: pybuild base:311: cd /build/reproducible-path/ipykernel-6.29.5/.pybuild/cpython3_3.12/build; python3.12 -m pytest -v -k 'not test_init_ipc_socket'
 /usr/lib/python3/dist-packages/pytest_asyncio/plugin.py:208: PytestDeprecationWarning: The configuration option "asyncio_default_fixture_loop_scope" is unset.
 The event loop scope for asynchronous fixtures will default to the fixture caching scope. Future versions of pytest-asyncio will default the loop scope for asynchronous fixtures to function scope. Set the default fixture loop scope explicitly in order to avoid unexpected behavior in the future. Valid fixture loop scopes are: "function", "class", "module", "package", "session"
@@ -1072,11 +1108,11 @@
 rootdir: /build/reproducible-path/ipykernel-6.29.5/.pybuild/cpython3_3.12/build
 configfile: pyproject.toml
 testpaths: tests, tests/inprocess
-plugins: timeout-2.3.1, asyncio-0.24.0a1, typeguard-4.4.1, flaky-3.8.1
+plugins: asyncio-0.24.0a1, flaky-3.8.1, typeguard-4.4.1, timeout-2.3.1
+asyncio: mode=Mode.AUTO, default_loop_scope=None
 timeout: 300.0s
 timeout method: signal
 timeout func_only: False
-asyncio: mode=Mode.AUTO, default_loop_scope=None
 collecting ... collected 12 items
 
 tests/inprocess/test_kernel.py::test_with_cell_id PASSED                 [  8%]
@@ -1108,20 +1144,20 @@
 
 ===End Flaky Test Report===
 ============================= slowest 10 durations =============================
-1.64s call     tests/inprocess/test_kernelmanager.py::InProcessKernelManagerTestCase::test_complete
-0.79s setup    tests/inprocess/test_kernel.py::test_with_cell_id
-0.25s call     tests/inprocess/test_kernelmanager.py::InProcessKernelManagerTestCase::test_history
-0.25s call     tests/inprocess/test_kernelmanager.py::InProcessKernelManagerTestCase::test_inspect
+2.01s call     tests/inprocess/test_kernelmanager.py::InProcessKernelManagerTestCase::test_complete
+0.64s setup    tests/inprocess/test_kernel.py::test_with_cell_id
+0.26s setup    tests/inprocess/test_kernel.py::test_pylab
+0.24s call     tests/inprocess/test_kernelmanager.py::InProcessKernelManagerTestCase::test_history
 0.23s call     tests/inprocess/test_kernelmanager.py::InProcessKernelManagerTestCase::test_execute
-0.22s setup    tests/inprocess/test_kernel.py::test_pylab
+0.23s call     tests/inprocess/test_kernelmanager.py::InProcessKernelManagerTestCase::test_inspect
 0.22s setup    tests/inprocess/test_kernel.py::test_stdout
-0.22s setup    tests/inprocess/test_kernel.py::test_raw_input
-0.22s setup    tests/inprocess/test_kernel.py::test_do_execute
 0.22s setup    tests/inprocess/test_kernel.py::test_getpass_stream
+0.22s setup    tests/inprocess/test_kernel.py::test_do_execute
+0.22s setup    tests/inprocess/test_kernel.py::test_raw_input
 =========================== short test summary info ============================
 SKIPPED [1] tests/inprocess/test_kernel.py:58: This test requires matplotlib
 SKIPPED [1] tests/inprocess/test_kernel.py:92: Currently don't capture during test as pytest does its own capturing
-=================== 10 passed, 2 skipped, 1 warning in 4.68s ===================
+=================== 10 passed, 2 skipped, 1 warning in 4.93s ===================
    create-stamp debian/debhelper-build-stamp
    dh_testroot -O--buildsystem=pybuild
    dh_prep -O--buildsystem=pybuild
@@ -1131,9 +1167,9 @@
    debian/rules execute_after_dh_install
 make[1]: Entering directory '/build/reproducible-path/ipykernel-6.29.5'
 python3 -m ipykernel install --prefix=/build/reproducible-path/ipykernel-6.29.5/debian/python3-ipykernel/usr
-/usr/lib/python3/dist-packages/IPython/paths.py:69: UserWarning: IPython parent '/nonexistent/first-build' is not a writable location, using a temp directory.
+/usr/lib/python3/dist-packages/IPython/paths.py:69: UserWarning: IPython parent '/nonexistent/second-build' is not a writable location, using a temp directory.
   warn("IPython parent '{0}' is not a writable location,"
-[InstallIPythonKernelSpecApp] WARNING | Installing to /build/reproducible-path/ipykernel-6.29.5/debian/python3-ipykernel/usr/share/jupyter/kernels, which is not in ['/nonexistent/first-build/.local/share/jupyter/kernels', '/usr/local/share/jupyter/kernels', '/usr/share/jupyter/kernels', '/tmp/tmpz8q7qakj/kernels']. The kernelspec may not be found.
+[InstallIPythonKernelSpecApp] WARNING | Installing to /build/reproducible-path/ipykernel-6.29.5/debian/python3-ipykernel/usr/share/jupyter/kernels, which is not in ['/nonexistent/second-build/.local/share/jupyter/kernels', '/usr/local/share/jupyter/kernels', '/usr/share/jupyter/kernels', '/tmp/tmp9si9kvje/kernels']. The kernelspec may not be found.
 Installed kernelspec python3 in /build/reproducible-path/ipykernel-6.29.5/debian/python3-ipykernel/usr/share/jupyter/kernels/python3
 find debian/python3-ipykernel -name COPYING.md -delete
 make[1]: Leaving directory '/build/reproducible-path/ipykernel-6.29.5'
@@ -1162,12 +1198,14 @@
 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/26917/tmp/hooks/B01_cleanup starting
+I: user script /srv/workspace/pbuilder/26917/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/19099 and its subdirectories
-I: Current time: Sun Dec 15 18:18:09 -12 2024
-I: pbuilder-time-stamp: 1734329889
+I: removing directory /srv/workspace/pbuilder/26917 and its subdirectories
+I: Current time: Mon Dec 16 20:22:21 +14 2024
+I: pbuilder-time-stamp: 1734330141