Diff of the two buildlogs:

--
--- b1/build.log	2023-04-24 21:46:44.443346669 +0000
+++ b2/build.log	2023-04-24 21:48:13.023419054 +0000
@@ -1,6 +1,6 @@
 I: pbuilder: network access will be disabled during build
-I: Current time: Sun May 26 16:08:01 -12 2024
-I: pbuilder-time-stamp: 1716782881
+I: Current time: Tue Apr 25 11:46:48 +14 2023
+I: pbuilder-time-stamp: 1682372808
 I: Building the build Environment
 I: extracting base tarball [/var/cache/pbuilder/bookworm-reproducible-base.tgz]
 I: copying local configuration
@@ -16,7 +16,7 @@
 I: copying [./ruby-oily-png_1.2.1~dfsg.orig.tar.gz]
 I: copying [./ruby-oily-png_1.2.1~dfsg-3.debian.tar.xz]
 I: Extracting source
-gpgv: Signature made Thu Nov 25 01:57:48 2021 -12
+gpgv: Signature made Fri Nov 26 03:57:48 2021 +14
 gpgv:                using RSA key 8ED6C3F8BAC9DB7FC130A870F823A2729883C97C
 gpgv:                issuer "kanashiro@debian.org"
 gpgv: Can't check signature: No public key
@@ -31,52 +31,84 @@
 dpkg-source: info: applying fix-tests-failing-on-32-bits-architectures.patch
 I: Not using root during the build.
 I: Installing the build-deps
-I: user script /srv/workspace/pbuilder/25947/tmp/hooks/D02_print_environment starting
+I: user script /srv/workspace/pbuilder/14478/tmp/hooks/D01_modify_environment starting
+debug: Running on codethink16-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 Apr 25 11:47 /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/14478/tmp/hooks/D01_modify_environment finished
+I: user script /srv/workspace/pbuilder/14478/tmp/hooks/D02_print_environment starting
 I: set
-  BUILDDIR='/build'
-  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
+  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=8'
-  DISTRIBUTION='bookworm'
-  HOME='/var/lib/jenkins'
-  HOST_ARCH='arm64'
+  DIRSTACK=()
+  DISTRIBUTION=bookworm
+  EUID=0
+  FUNCNAME=([0]="Echo" [1]="main")
+  GROUPS=()
+  HOME=/var/lib/jenkins
+  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='25947'
-  PS1='# '
-  PS2='> '
+  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=14478
   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.vce0mj3B/pbuilderrc_hNr0 --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.vce0mj3B/b1 --logfile b1/build.log ruby-oily-png_1.2.1~dfsg-3.dsc'
-  SUDO_GID='117'
-  SUDO_UID='110'
-  SUDO_USER='jenkins'
-  TERM='unknown'
-  TZ='/usr/share/zoneinfo/Etc/GMT+12'
-  USER='root'
-  USERNAME='root'
-  _='/usr/bin/systemd-run'
-  http_proxy='http://192.168.101.16:3128'
+  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.vce0mj3B/pbuilderrc_rRv1 --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.vce0mj3B/b2 --logfile b2/build.log --extrapackages usrmerge ruby-oily-png_1.2.1~dfsg-3.dsc'
+  SUDO_GID=117
+  SUDO_UID=110
+  SUDO_USER=jenkins
+  TERM=unknown
+  TZ=/usr/share/zoneinfo/Etc/GMT-14
+  UID=0
+  USER=root
+  USERNAME=root
+  _='I: set'
+  http_proxy=http://192.168.101.16:3128
 I: uname -a
-  Linux codethink11-arm64 4.15.0-209-generic #220-Ubuntu SMP Tue Mar 21 19:52:44 UTC 2023 aarch64 GNU/Linux
+  Linux i-capture-the-hostname 4.15.0-209-generic #220-Ubuntu SMP Tue Mar 21 19:52:44 UTC 2023 aarch64 GNU/Linux
 I: ls -l /bin
-  lrwxrwxrwx 1 root root 7 May 24 04:47 /bin -> usr/bin
-I: user script /srv/workspace/pbuilder/25947/tmp/hooks/D02_print_environment finished
+  lrwxrwxrwx 1 root root 7 Apr 24 00:25 /bin -> usr/bin
+I: user script /srv/workspace/pbuilder/14478/tmp/hooks/D02_print_environment finished
  -> Attempting to satisfy build-dependencies
  -> Creating pbuilder-satisfydepends-dummy package
 Package: pbuilder-satisfydepends-dummy
@@ -253,7 +285,7 @@
 Get: 131 http://deb.debian.org/debian bookworm/main arm64 ruby-rspec-expectations all 3.12.0c0e1m1s0-1 [89.5 kB]
 Get: 132 http://deb.debian.org/debian bookworm/main arm64 ruby-rspec-mocks all 3.12.0c0e1m1s0-1 [79.5 kB]
 Get: 133 http://deb.debian.org/debian bookworm/main arm64 ruby-rspec all 3.12.0c0e1m1s0-1 [5084 B]
-Fetched 45.6 MB in 2s (30.4 MB/s)
+Fetched 45.6 MB in 1s (35.1 MB/s)
 debconf: delaying package configuration, since apt-utils is not installed
 Selecting previously unselected package libpython3.11-minimal:arm64.
 (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 ... 19616 files and directories currently installed.)
@@ -808,8 +840,17 @@
 Writing extended state information...
 Building tag database...
  -> Finished parsing the build-deps
+Reading package lists...
+Building dependency tree...
+Reading state information...
+usrmerge is already the newest version (35).
+0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
 I: Building the package
-I: Running cd /build/ruby-oily-png-1.2.1~dfsg/ && 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  > ../ruby-oily-png_1.2.1~dfsg-3_source.changes
+I: user script /srv/workspace/pbuilder/14478/tmp/hooks/A99_set_merged_usr starting
+Re-configuring usrmerge...
+I: user script /srv/workspace/pbuilder/14478/tmp/hooks/A99_set_merged_usr finished
+hostname: Temporary failure in name resolution
+I: Running cd /build/ruby-oily-png-1.2.1~dfsg/ && 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  > ../ruby-oily-png_1.2.1~dfsg-3_source.changes
 dpkg-buildpackage: info: source package ruby-oily-png
 dpkg-buildpackage: info: source version 1.2.1~dfsg-3
 dpkg-buildpackage: info: source distribution unstable
@@ -838,7 +879,7 @@
    dh_prep -O--buildsystem=ruby
    dh_auto_install --destdir=debian/ruby-oily-png/ -O--buildsystem=ruby
 	dh_ruby --install /build/ruby-oily-png-1.2.1\~dfsg/debian/ruby-oily-png
-/usr/bin/ruby3.1 -S gem build --config-file /dev/null --verbose /tmp/d20240526-1106-1fcm5v/gemspec
+/usr/bin/ruby3.1 -S gem build --config-file /dev/null --verbose /tmp/d20230425-4977-jpm2up/gemspec
 Failed to load /dev/null because it doesn't contain valid YAML hash
 WARNING:  open-ended dependency on rake (>= 0, development) is not recommended
   use a bounded requirement, such as '~> x.y'
@@ -849,7 +890,7 @@
   Name: oily_png
   Version: 1.2.1
   File: oily_png-1.2.1.gem
-/usr/bin/ruby3.1 -S gem install --config-file /dev/null --verbose --local --verbose --no-document --ignore-dependencies --install-dir debian/ruby-oily-png/usr/lib/aarch64-linux-gnu/rubygems-integration/3.1.0 /tmp/d20240526-1106-1fcm5v/oily_png-1.2.1.gem
+/usr/bin/ruby3.1 -S gem install --config-file /dev/null --verbose --local --verbose --no-document --ignore-dependencies --install-dir debian/ruby-oily-png/usr/lib/aarch64-linux-gnu/rubygems-integration/3.1.0 /tmp/d20230425-4977-jpm2up/oily_png-1.2.1.gem
 Failed to load /dev/null because it doesn't contain valid YAML hash
 /build/ruby-oily-png-1.2.1~dfsg/debian/ruby-oily-png/usr/lib/aarch64-linux-gnu/rubygems-integration/3.1.0/gems/oily_png-1.2.1/ext/oily_png/color.c
 /build/ruby-oily-png-1.2.1~dfsg/debian/ruby-oily-png/usr/lib/aarch64-linux-gnu/rubygems-integration/3.1.0/gems/oily_png-1.2.1/ext/oily_png/color.h
@@ -870,7 +911,7 @@
 /build/ruby-oily-png-1.2.1~dfsg/debian/ruby-oily-png/usr/lib/aarch64-linux-gnu/rubygems-integration/3.1.0/gems/oily_png-1.2.1/tasks/testing.rake
 Building native extensions. This could take a while...
 current directory: /build/ruby-oily-png-1.2.1~dfsg/debian/ruby-oily-png/usr/lib/aarch64-linux-gnu/rubygems-integration/3.1.0/gems/oily_png-1.2.1/ext/oily_png
-["/usr/bin/ruby3.1", "-I", "/usr/lib/ruby/vendor_ruby", "-r", "./siteconf20240526-1165-1ez99j.rb", "extconf.rb"]
+["/usr/bin/ruby3.1", "-I", "/usr/lib/ruby/vendor_ruby", "-r", "./siteconf20230425-5567-6afydh.rb", "extconf.rb"]
 creating Makefile
 current directory: /build/ruby-oily-png-1.2.1~dfsg/debian/ruby-oily-png/usr/lib/aarch64-linux-gnu/rubygems-integration/3.1.0/gems/oily_png-1.2.1/ext/oily_png
 ["make", "V=1", "CC=gcc -fdebug-prefix-map=/build/ruby-oily-png-1.2.1~dfsg=.", "CXX=g++ -fdebug-prefix-map=/build/ruby-oily-png-1.2.1~dfsg=.", "DESTDIR=", "clean"]
@@ -893,12 +934,12 @@
 current directory: /build/ruby-oily-png-1.2.1~dfsg/debian/ruby-oily-png/usr/lib/aarch64-linux-gnu/rubygems-integration/3.1.0/gems/oily_png-1.2.1/ext/oily_png
 ["make", "V=1", "CC=gcc -fdebug-prefix-map=/build/ruby-oily-png-1.2.1~dfsg=.", "CXX=g++ -fdebug-prefix-map=/build/ruby-oily-png-1.2.1~dfsg=.", "DESTDIR=", "install"]
 make[1]: Entering directory '/build/ruby-oily-png-1.2.1~dfsg/debian/ruby-oily-png/usr/lib/aarch64-linux-gnu/rubygems-integration/3.1.0/gems/oily_png-1.2.1/ext/oily_png'
-/bin/mkdir -p . ./.gem.20240526-1165-2e33bb/oily_png
+/bin/mkdir -p . ./.gem.20230425-5567-j3ni0s/oily_png
 exit > .sitearchdir.-.oily_png.time
-/usr/bin/install -c -m 0755 oily_png.so ./.gem.20240526-1165-2e33bb/oily_png
+/usr/bin/install -c -m 0755 oily_png.so ./.gem.20230425-5567-j3ni0s/oily_png
 make[1]: Leaving directory '/build/ruby-oily-png-1.2.1~dfsg/debian/ruby-oily-png/usr/lib/aarch64-linux-gnu/rubygems-integration/3.1.0/gems/oily_png-1.2.1/ext/oily_png'
 current directory: /build/ruby-oily-png-1.2.1~dfsg/debian/ruby-oily-png/usr/lib/aarch64-linux-gnu/rubygems-integration/3.1.0/gems/oily_png-1.2.1/ext/oily_png
-/usr/bin/ruby3.1 -I /usr/lib/ruby/vendor_ruby -r ./siteconf20240526-1165-1ez99j.rb extconf.rb
+/usr/bin/ruby3.1 -I /usr/lib/ruby/vendor_ruby -r ./siteconf20230425-5567-6afydh.rb extconf.rb
 current directory: /build/ruby-oily-png-1.2.1~dfsg/debian/ruby-oily-png/usr/lib/aarch64-linux-gnu/rubygems-integration/3.1.0/gems/oily_png-1.2.1/ext/oily_png
 make V\=1 CC\=gcc\ -fdebug-prefix-map\=/build/ruby-oily-png-1.2.1\~dfsg\=. CXX\=g++\ -fdebug-prefix-map\=/build/ruby-oily-png-1.2.1\~dfsg\=. DESTDIR\= clean
 current directory: /build/ruby-oily-png-1.2.1~dfsg/debian/ruby-oily-png/usr/lib/aarch64-linux-gnu/rubygems-integration/3.1.0/gems/oily_png-1.2.1/ext/oily_png
@@ -946,7 +987,7 @@
     should compose pixels correctly
     should compose colors exactly the same as ChunkyPNG
   #euclidean_distance_rgba
-    is expected to eq 249.81793370372753
+    is expected to eq 238.34428879249447
     when both colors are the same
       is expected to eq 0
 
@@ -1185,7 +1226,7 @@
      # Temporarily skipped with xdescribe
      # ./spec/resampling_spec.rb:55
 
-Finished in 0.83498 seconds (files took 0.61772 seconds to load)
+Finished in 0.67086 seconds (files took 0.47696 seconds to load)
 146 examples, 0 failures, 18 pending
 
 
@@ -1228,12 +1269,14 @@
 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/14478/tmp/hooks/B01_cleanup starting
+I: user script /srv/workspace/pbuilder/14478/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/25947 and its subdirectories
-I: Current time: Sun May 26 16:09:42 -12 2024
-I: pbuilder-time-stamp: 1716782982
+I: removing directory /srv/workspace/pbuilder/14478 and its subdirectories
+I: Current time: Tue Apr 25 11:48:11 +14 2023
+I: pbuilder-time-stamp: 1682372891