Bug#1044840: fst: Fails to build source after successful build

[Lucas Nussbaum <lucas@debian.org>]

Source: fst
Version: 0.122.0-1
Severity: minor
Tags: trixie sid ftbfs
User: lucas@debian.org
Usertags: ftbfs-sab-20230813 ftbfs-source-after-build
User: debian-qa@lists.debian.org
Usertags: qa-doublebuild

Hi,

This package fails to build a source package after a successful build
(dpkg-buildpackage ; dpkg-buildpackage -S).

This is probably a clear violation of Debian Policy section 4.9 (clean target),
but this is filed as severity:minor for now, because a discussion on
debian-devel showed that we might want to revisit the requirement of a working
'clean' target.

More information about this class of issues, included common problems and
solutions, is available at
https://wiki.debian.org/qa.debian.org/FTBFS/SourceAfterBuild

Relevant part of the build log:
> cd /<<PKGBUILDDIR>> && runuser -u user42 -- dpkg-buildpackage --sanitize-env -us -uc -rfakeroot -S
> ---------------------------------------------------------------------------------------------------------------
> 
> dpkg-buildpackage: info: source package fst
> dpkg-buildpackage: info: source version 0.122.0-1
> dpkg-buildpackage: info: source distribution unstable
> dpkg-buildpackage: info: source changed by IOhannes m zmölnig (Debian/GNU) <umlaeute@debian.org>
>  dpkg-source --before-build .
>  debian/rules clean
> dh clean
>    dh_clean
>  dpkg-source -b .
> dpkg-source: info: using source format '3.0 (quilt)'
> dpkg-source: info: building fst using existing ./fst_0.122.0.orig.tar.bz2
> dpkg-source: error: cannot represent change to tests/c_test: binary file contents changed
> dpkg-source: error: add tests/c_test in debian/source/include-binaries if you want to store the modified binary in the debian tarball
> dpkg-source: warning: executable mode 0755 of 'tests/c_test' will not be represented in diff
> dpkg-source: error: cannot represent change to tests/cxx_test: binary file contents changed
> dpkg-source: error: add tests/cxx_test in debian/source/include-binaries if you want to store the modified binary in the debian tarball
> dpkg-source: warning: executable mode 0755 of 'tests/cxx_test' will not be represented in diff
> dpkg-source: error: unrepresentable changes to source
> dpkg-buildpackage: error: dpkg-source -b . subprocess returned exit status 1
> 
> E: Command 'cd /<<PKGBUILDDIR>> && runuser -u user42 -- dpkg-buildpackage --sanitize-env -us -uc -rfakeroot -S' failed to run.


The full build log is available from:
http://qa-logs.debian.net/2023/08/13/fst_0.122.0-1_unstable.log

If you reassign this bug to another package, please mark it as 'affects'-ing
this package. See https://www.debian.org/Bugs/server-control#affects

If you fail to reproduce this, please provide a build log and diff it with mine
so that we can identify if something relevant changed in the meantime.