Diff of the two buildlogs:

--
--- b1/build.log	2024-05-16 02:47:48.967651618 +0000
+++ b2/build.log	2024-05-16 02:49:23.999610133 +0000
@@ -1,6 +1,6 @@
 I: pbuilder: network access will be disabled during build
-I: Current time: Wed May 15 14:47:09 -12 2024
-I: pbuilder-time-stamp: 1715827629
+I: Current time: Thu May 16 16:47:52 +14 2024
+I: pbuilder-time-stamp: 1715827672
 I: Building the build Environment
 I: extracting base tarball [/var/cache/pbuilder/trixie-reproducible-base.tgz]
 I: copying local configuration
@@ -33,52 +33,84 @@
 dpkg-source: info: applying drop-Wno-implicit-function-declaration.patch
 I: using fakeroot in build.
 I: Installing the build-deps
-I: user script /srv/workspace/pbuilder/2459329/tmp/hooks/D02_print_environment starting
+I: user script /srv/workspace/pbuilder/699387/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 May 16 02:48 /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/699387/tmp/hooks/D01_modify_environment finished
+I: user script /srv/workspace/pbuilder/699387/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]="21" [3]="1" [4]="release" [5]="aarch64-unknown-linux-gnu")
+  BASH_VERSION='5.2.21(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='trixie'
-  HOME='/root'
-  HOST_ARCH='arm64'
+  DIRSTACK=()
+  DISTRIBUTION=trixie
+  EUID=0
+  FUNCNAME=([0]="Echo" [1]="main")
+  GROUPS=()
+  HOME=/root
+  HOSTNAME=i-capture-the-hostname
+  HOSTTYPE=aarch64
+  HOST_ARCH=arm64
   IFS=' 	
   '
-  INVOCATION_ID='37216b31f6da4b7f9e9a8556fa295597'
-  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='2459329'
-  PS1='# '
-  PS2='> '
+  INVOCATION_ID=28aef760b56543d8b8a71345012c65f0
+  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=699387
   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.OtuktaXl/pbuilderrc_SD9O --distribution trixie --hookdir /etc/pbuilder/first-build-hooks --debbuildopts -b --basetgz /var/cache/pbuilder/trixie-reproducible-base.tgz --buildresult /srv/reproducible-results/rbuild-debian/r-b-build.OtuktaXl/b1 --logfile b1/build.log radvd_2.19-2.dsc'
-  SUDO_GID='109'
-  SUDO_UID='104'
-  SUDO_USER='jenkins'
-  TERM='unknown'
-  TZ='/usr/share/zoneinfo/Etc/GMT+12'
-  USER='root'
-  _='/usr/bin/systemd-run'
-  http_proxy='http://192.168.101.4:3128'
+  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.OtuktaXl/pbuilderrc_grGg --distribution trixie --hookdir /etc/pbuilder/rebuild-hooks --debbuildopts -b --basetgz /var/cache/pbuilder/trixie-reproducible-base.tgz --buildresult /srv/reproducible-results/rbuild-debian/r-b-build.OtuktaXl/b2 --logfile b2/build.log radvd_2.19-2.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://192.168.101.4:3128
 I: uname -a
-  Linux codethink02-arm64 6.1.0-21-cloud-arm64 #1 SMP Debian 6.1.90-1 (2024-05-03) aarch64 GNU/Linux
+  Linux i-capture-the-hostname 6.1.0-21-cloud-arm64 #1 SMP Debian 6.1.90-1 (2024-05-03) aarch64 GNU/Linux
 I: ls -l /bin
-  lrwxrwxrwx 1 root root 7 May 15 11:24 /bin -> usr/bin
-I: user script /srv/workspace/pbuilder/2459329/tmp/hooks/D02_print_environment finished
+  lrwxrwxrwx 1 root root 7 May 14 11:23 /bin -> usr/bin
+I: user script /srv/workspace/pbuilder/699387/tmp/hooks/D02_print_environment finished
  -> Attempting to satisfy build-dependencies
  -> Creating pbuilder-satisfydepends-dummy package
 Package: pbuilder-satisfydepends-dummy
@@ -165,7 +197,7 @@
 Get: 39 http://deb.debian.org/debian trixie/main arm64 pkgconf-bin arm64 1.8.1-1+b2 [29.3 kB]
 Get: 40 http://deb.debian.org/debian trixie/main arm64 pkgconf arm64 1.8.1-1+b2 [26.2 kB]
 Get: 41 http://deb.debian.org/debian trixie/main arm64 pkg-config arm64 1.8.1-1+b2 [14.0 kB]
-Fetched 20.5 MB in 0s (121 MB/s)
+Fetched 20.5 MB in 0s (89.5 MB/s)
 debconf: delaying package configuration, since apt-utils is not installed
 Selecting previously unselected package m4.
 (Reading database ... 
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(Reading database ... 100%
(Reading database ... 19744 files and directories currently installed.)
@@ -350,7 +382,11 @@
 fakeroot is already the newest version (1.33-1).
 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
 I: Building the package
-I: Running cd /build/reproducible-path/radvd-2.19/ && 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  > ../radvd_2.19-2_source.changes
+I: user script /srv/workspace/pbuilder/699387/tmp/hooks/A99_set_merged_usr starting
+Not re-configuring usrmerge for trixie
+I: user script /srv/workspace/pbuilder/699387/tmp/hooks/A99_set_merged_usr finished
+hostname: Name or service not known
+I: Running cd /build/reproducible-path/radvd-2.19/ && 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  > ../radvd_2.19-2_source.changes
 dpkg-buildpackage: info: source package radvd
 dpkg-buildpackage: info: source version 1:2.19-2
 dpkg-buildpackage: info: source distribution unstable
@@ -553,10 +589,10 @@
    42 |         strncpy(ifr.ifr_name, iface->props.name, IFNAMSIZ - 1);
       |         ^
 gcc -DINET6=1 -DLOG_FACILITY=LOG_DAEMON -DPATH_RADVD_CONF=\"/etc/radvd.conf\" -DPATH_RADVD_LOG=\"/var/log/radvd.log\" -DPATH_RADVD_PID=\"/run/radvd.pid\" -DVERSION=\"2.19\" -I.   -Wdate-time -D_FORTIFY_SOURCE=2 -fno-strict-aliasing -Wall -Wcast-qual -Wmissing-declarations -Wmissing-prototypes -Wpointer-arith -Wstrict-prototypes -Wno-strict-aliasing -Wno-cast-align -Wno-strict-overflow -fstack-protector -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/radvd-2.19=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -mbranch-protection=standard -c -o netlink.o netlink.c
-/bin/bash ./ylwrap gram.y y.tab.c gram.c y.tab.h `echo gram.c | sed -e s/cc$/hh/ -e s/cpp$/hpp/ -e s/cxx$/hxx/ -e s/c++$/h++/ -e s/c$/h/` y.output gram.output -- bison -y -d 
+/bin/sh ./ylwrap gram.y y.tab.c gram.c y.tab.h `echo gram.c | sed -e s/cc$/hh/ -e s/cpp$/hpp/ -e s/cxx$/hxx/ -e s/c++$/h++/ -e s/c$/h/` y.output gram.output -- bison -y -d 
 updating gram.h
 gcc -DINET6=1 -DLOG_FACILITY=LOG_DAEMON -DPATH_RADVD_CONF=\"/etc/radvd.conf\" -DPATH_RADVD_LOG=\"/var/log/radvd.log\" -DPATH_RADVD_PID=\"/run/radvd.pid\" -DVERSION=\"2.19\" -I.   -Wdate-time -D_FORTIFY_SOURCE=2 -fno-strict-aliasing -Wall -Wcast-qual -Wmissing-declarations -Wmissing-prototypes -Wpointer-arith -Wstrict-prototypes -Wno-strict-aliasing -Wno-cast-align -Wno-strict-overflow -fstack-protector -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/radvd-2.19=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -mbranch-protection=standard -c -o gram.o gram.c
-/bin/bash ./ylwrap scanner.l lex.yy.c scanner.c -- flex  
+/bin/sh ./ylwrap scanner.l lex.yy.c scanner.c -- flex  
 gcc -DINET6=1 -DLOG_FACILITY=LOG_DAEMON -DPATH_RADVD_CONF=\"/etc/radvd.conf\" -DPATH_RADVD_LOG=\"/var/log/radvd.log\" -DPATH_RADVD_PID=\"/run/radvd.pid\" -DVERSION=\"2.19\" -I.   -Wdate-time -D_FORTIFY_SOURCE=2 -fno-strict-aliasing -Wall -Wcast-qual -Wmissing-declarations -Wmissing-prototypes -Wpointer-arith -Wstrict-prototypes -Wno-strict-aliasing -Wno-cast-align -Wno-strict-overflow -fstack-protector -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/radvd-2.19=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -mbranch-protection=standard -c -o scanner.o scanner.c
 rm -f libradvd-parser.a
 ar cru libradvd-parser.a gram.o scanner.o 
@@ -644,12 +680,14 @@
 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/699387/tmp/hooks/B01_cleanup starting
+I: user script /srv/workspace/pbuilder/699387/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/2459329 and its subdirectories
-I: Current time: Wed May 15 14:47:47 -12 2024
-I: pbuilder-time-stamp: 1715827667
+I: removing directory /srv/workspace/pbuilder/699387 and its subdirectories
+I: Current time: Thu May 16 16:49:22 +14 2024
+I: pbuilder-time-stamp: 1715827762