Diff of the two buildlogs:

--
--- b1/build.log	2024-05-15 06:37:55.430542717 +0000
+++ b2/build.log	2024-05-15 06:42:07.495809977 +0000
@@ -1,6 +1,6 @@
 I: pbuilder: network access will be disabled during build
-I: Current time: Tue May 14 18:32:46 -12 2024
-I: pbuilder-time-stamp: 1715754766
+I: Current time: Wed Jun 18 03:00:59 +14 2025
+I: pbuilder-time-stamp: 1750165259
 I: Building the build Environment
 I: extracting base tarball [/var/cache/pbuilder/trixie-reproducible-base.tgz]
 I: copying local configuration
@@ -27,54 +27,86 @@
 dpkg-source: info: unpacking coq-stdpp_1.9.0-1.debian.tar.xz
 I: Not using root during the build.
 I: Installing the build-deps
-I: user script /srv/workspace/pbuilder/44709/tmp/hooks/D02_print_environment starting
+I: user script /srv/workspace/pbuilder/115708/tmp/hooks/D01_modify_environment starting
+debug: Running on ionos16-i386.
+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 Jun 17 13:01 /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/115708/tmp/hooks/D01_modify_environment finished
+I: user script /srv/workspace/pbuilder/115708/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='i386'
-  DEBIAN_FRONTEND='noninteractive'
-  DEB_BUILD_OPTIONS='buildinfo=+all reproducible=+all parallel=11 '
-  DISTRIBUTION='trixie'
-  HOME='/root'
-  HOST_ARCH='i386'
+  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]="i686-pc-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=i386
+  DEBIAN_FRONTEND=noninteractive
+  DEB_BUILD_OPTIONS='buildinfo=+all reproducible=+all parallel=21 '
+  DIRSTACK=()
+  DISTRIBUTION=trixie
+  EUID=0
+  FUNCNAME=([0]="Echo" [1]="main")
+  GROUPS=()
+  HOME=/root
+  HOSTNAME=i-capture-the-hostname
+  HOSTTYPE=i686
+  HOST_ARCH=i386
   IFS=' 	
   '
-  INVOCATION_ID='d863047530ff4977951ea596512950d5'
-  LANG='C'
-  LANGUAGE='en_US:en'
-  LC_ALL='C'
-  LD_LIBRARY_PATH='/usr/lib/libeatmydata'
-  LD_PRELOAD='libeatmydata.so'
-  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='44709'
-  PS1='# '
-  PS2='> '
+  INVOCATION_ID=1802d4eece6543a49e4768c41e28987b
+  LANG=C
+  LANGUAGE=de_CH:de
+  LC_ALL=C
+  LD_LIBRARY_PATH=/usr/lib/libeatmydata
+  LD_PRELOAD=libeatmydata.so
+  MACHTYPE=i686-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=115708
   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.PMmGhGxY/pbuilderrc_pQQQ --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.PMmGhGxY/b1 --logfile b1/build.log coq-stdpp_1.9.0-1.dsc'
-  SUDO_GID='112'
-  SUDO_UID='107'
-  SUDO_USER='jenkins'
-  TERM='unknown'
-  TZ='/usr/share/zoneinfo/Etc/GMT+12'
-  USER='root'
-  _='/usr/bin/systemd-run'
-  http_proxy='http://46.16.76.132:3128'
+  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.PMmGhGxY/pbuilderrc_nz20 --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.PMmGhGxY/b2 --logfile b2/build.log coq-stdpp_1.9.0-1.dsc'
+  SUDO_GID=112
+  SUDO_UID=107
+  SUDO_USER=jenkins
+  TERM=unknown
+  TZ=/usr/share/zoneinfo/Etc/GMT-14
+  UID=0
+  USER=root
+  _='I: set'
+  http_proxy=http://213.165.73.152:3128
 I: uname -a
-  Linux ionos2-i386 6.1.0-21-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.1.90-1 (2024-05-03) x86_64 GNU/Linux
+  Linux i-capture-the-hostname 6.1.0-21-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.1.90-1 (2024-05-03) x86_64 GNU/Linux
 I: ls -l /bin
-  lrwxrwxrwx 1 root root 7 May 13 11:24 /bin -> usr/bin
-I: user script /srv/workspace/pbuilder/44709/tmp/hooks/D02_print_environment finished
+  lrwxrwxrwx 1 root root 7 Jun 14 18:01 /bin -> usr/bin
+I: user script /srv/workspace/pbuilder/115708/tmp/hooks/D02_print_environment finished
  -> Attempting to satisfy build-dependencies
  -> Creating pbuilder-satisfydepends-dummy package
 Package: pbuilder-satisfydepends-dummy
@@ -185,7 +217,7 @@
 Get: 63 http://deb.debian.org/debian trixie/main i386 libgmp3-dev i386 2:6.3.0+dfsg-2+b1 [322 kB]
 Get: 64 http://deb.debian.org/debian trixie/main i386 libzarith-ocaml-dev i386 1.13-2+b1 [105 kB]
 Get: 65 http://deb.debian.org/debian trixie/main i386 libcoq-core-ocaml-dev i386 8.18.0+dfsg-1 [44.1 MB]
-Fetched 307 MB in 5s (66.3 MB/s)
+Fetched 307 MB in 6s (52.3 MB/s)
 debconf: delaying package configuration, since apt-utils is not installed
 Selecting previously unselected package libpython3.11-minimal:i386.
 (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 ... 19684 files and directories currently installed.)
@@ -410,8 +442,8 @@
 Setting up tzdata (2024a-4) ...
 
 Current default time zone: 'Etc/UTC'
-Local time is now:      Wed May 15 06:33:25 UTC 2024.
-Universal Time is now:  Wed May 15 06:33:25 UTC 2024.
+Local time is now:      Tue Jun 17 13:01:33 UTC 2025.
+Universal Time is now:  Tue Jun 17 13:01:33 UTC 2025.
 Run 'dpkg-reconfigure tzdata' if you wish to change it.
 
 Setting up autotools-dev (20220109.1) ...
@@ -472,7 +504,11 @@
 Building tag database...
  -> Finished parsing the build-deps
 I: Building the package
-I: Running cd /build/reproducible-path/coq-stdpp-1.9.0/ && 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  > ../coq-stdpp_1.9.0-1_source.changes
+I: user script /srv/workspace/pbuilder/115708/tmp/hooks/A99_set_merged_usr starting
+Not re-configuring usrmerge for trixie
+I: user script /srv/workspace/pbuilder/115708/tmp/hooks/A99_set_merged_usr finished
+hostname: Name or service not known
+I: Running cd /build/reproducible-path/coq-stdpp-1.9.0/ && 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  > ../coq-stdpp_1.9.0-1_source.changes
 dpkg-buildpackage: info: source package coq-stdpp
 dpkg-buildpackage: info: source version 1.9.0-1
 dpkg-buildpackage: info: source distribution unstable
@@ -518,9 +554,8 @@
 COQC stdpp/proof_irrel.v
 COQC stdpp/decidable.v
 COQC stdpp/tactics.v
-COQC stdpp/option.v
-COQTEST tests/tactics_more.v (ref: tests/tactics_more.ref)
 COQC stdpp/orders.v
+COQC stdpp/option.v
 COQC stdpp/numbers.v
 COQC stdpp/list.v
 COQC stdpp/list_numbers.v
@@ -532,47 +567,48 @@
 COQC stdpp/sets.v
 COQC stdpp/relations.v
 COQC stdpp/fin_sets.v
-COQC stdpp/listset.v
-COQC stdpp/lexico.v
-COQC stdpp/prelude.v
-COQC stdpp/strings.v
-COQTEST tests/length.v (ref: tests/length.ref)
-COQTEST tests/decidable.v (ref: tests/decidable.ref)
-COQTEST tests/list.v (ref: tests/list.ref)
-COQTEST tests/tactics.v (ref: tests/tactics.ref)
-COQTEST tests/is_closed_term.v (ref: tests/is_closed_term.ref)
-COQTEST tests/eunify.v (ref: tests/eunify.ref)
-COQC stdpp_unstable/bitblast.v
-COQC stdpp_unstable/bitvector.v
-COQC stdpp_unstable/bitvector_tactics.v
-COQTEST tests/bitvector_tactics.v (ref: tests/bitvector_tactics.ref)
-COQTEST tests/numbers.v (ref: tests/numbers.ref)
 COQC stdpp/fin_maps.v
-COQC stdpp/pretty.v
-COQC stdpp/infinite.v
 COQC stdpp/fin_map_dom.v
+COQC stdpp/strings.v
 COQC stdpp/mapset.v
 COQC stdpp/pmap.v
+COQC stdpp/pretty.v
+COQC stdpp/infinite.v
 COQC stdpp/gmap.v
+COQTEST tests/fin_maps.v (ref: tests/fin_maps.ref)
+COQC stdpp/listset.v
+COQC stdpp/lexico.v
+COQC stdpp/prelude.v
 COQC stdpp/ssreflect.v
 COQC stdpp/gmultiset.v
 COQTEST tests/notation.v (ref: tests/notation.ref)
-COQC stdpp/coPset.v
-COQC stdpp/namespaces.v
-COQTEST tests/solve_ndisj.v (ref: tests/solve_ndisj.ref)
-COQTEST tests/pretty.v (ref: tests/pretty.ref)
+COQTEST tests/length.v (ref: tests/length.ref)
+COQTEST tests/is_closed_term.v (ref: tests/is_closed_term.ref)
+COQC stdpp/telescopes.v
+COQTEST tests/telescopes.v (ref: tests/telescopes.ref)
 COQTEST tests/fin.v (ref: tests/fin.ref)
 COQTEST tests/universes.v (ref: tests/universes.ref)
-COQTEST tests/multiset_solver.v (ref: tests/multiset_solver.ref)
+COQTEST tests/decidable.v (ref: tests/decidable.ref)
+COQTEST tests/pretty.v (ref: tests/pretty.ref)
 COQC stdpp/propset.v
 COQTEST tests/proper.v (ref: tests/proper.ref)
-COQTEST tests/typeclasses.v (ref: tests/typeclasses.ref)
+COQC stdpp_unstable/bitblast.v
+COQC stdpp_unstable/bitvector.v
+COQC stdpp_unstable/bitvector_tactics.v
+COQTEST tests/bitvector_tactics.v (ref: tests/bitvector_tactics.ref)
+COQTEST tests/bitvector.v (ref: tests/bitvector.ref)
+COQTEST tests/multiset_solver.v (ref: tests/multiset_solver.ref)
+COQTEST tests/tactics_more.v (ref: tests/tactics_more.ref)
+COQC stdpp/coPset.v
+COQC stdpp/namespaces.v
+COQTEST tests/solve_ndisj.v (ref: tests/solve_ndisj.ref)
 COQTEST tests/bitblast.v (ref: tests/bitblast.ref)
+COQTEST tests/tactics.v (ref: tests/tactics.ref)
+COQTEST tests/typeclasses.v (ref: tests/typeclasses.ref)
+COQTEST tests/numbers.v (ref: tests/numbers.ref)
 COQTEST tests/sets.v (ref: tests/sets.ref)
-COQTEST tests/bitvector.v (ref: tests/bitvector.ref)
-COQC stdpp/telescopes.v
-COQTEST tests/telescopes.v (ref: tests/telescopes.ref)
-COQTEST tests/fin_maps.v (ref: tests/fin_maps.ref)
+COQTEST tests/eunify.v (ref: tests/eunify.ref)
+COQTEST tests/list.v (ref: tests/list.ref)
 COQC stdpp/boolset.v
 COQC stdpp/stringmap.v
 COQC stdpp/zmap.v
@@ -591,7 +627,7 @@
 make[2]: Leaving directory '/build/reproducible-path/coq-stdpp-1.9.0'
 make[1]: Leaving directory '/build/reproducible-path/coq-stdpp-1.9.0'
    dh_auto_test
-	make -j11 test
+	make -j21 test
 make[1]: Entering directory '/build/reproducible-path/coq-stdpp-1.9.0'
 make[2]: Entering directory '/build/reproducible-path/coq-stdpp-1.9.0'
 make[2]: Nothing to be done for 'test'.
@@ -796,12 +832,14 @@
 dpkg-buildpackage: info: binary-only upload (no source included)
 dpkg-genchanges: info: including full source code in upload
 I: copying local configuration
+I: user script /srv/workspace/pbuilder/115708/tmp/hooks/B01_cleanup starting
+I: user script /srv/workspace/pbuilder/115708/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/44709 and its subdirectories
-I: Current time: Tue May 14 18:37:54 -12 2024
-I: pbuilder-time-stamp: 1715755074
+I: removing directory /srv/workspace/pbuilder/115708 and its subdirectories
+I: Current time: Wed Jun 18 03:05:06 +14 2025
+I: pbuilder-time-stamp: 1750165506