The build path is embedded in /usr/bin/gwaei:

https://tests.reproducible-builds.org/debian/rb-pkg/unstable/amd64/diffoscope-results/gwaei.html

  /build/1st/gwaei-3.6.2/src/gwaei/gwaei.c:47
  vs.
  /build/2/gwaei-3.6.2/2nd/src/gwaei/gwaei.c:47

The attached patch fixes this by adding the -ffile-prefix-map argument
to CFLAGS in debian/rules.

With this patch applied gwaei should build reproducibly on
tests.reproducible-builds.org!

Thanks for maintaining gwaei!

live well,
  vagrant

Dear Maintainer,

Because Debian builds packages from a fixed build path, neither the 'reprotest'
utility in Salsa-CI, nor the Reproducible Builds team's package test
infrastructure for Debian[1] currently check for equivalent binary package
output from differing source package build paths.

This means that your package will pass current reproducibility tests; however
we believe that source code and/or build steps still embed the build path into
the binary package output, making it more difficult than necessary for
independent consumers to check the integrity of those packages by rebuilding
them themselves.

As a result, this bugreport will remain open and be re-assigned the 'wishlist'
severity[2].

For more information about build paths and how they can affect reproducibility,
please refer to: https://reproducible-builds.org/docs/build-path/

Thanks,
James

[1] - https://tests.reproducible-builds.org/debian/reproducible.html

[2] - https://www.debian.org/Bugs/Developer#severities

A correction for a mistake in my previous message:

Currently the 'reprotest' job in Salsa-CI does in fact continue to exercise
variations of the build-path, and will fail if it builds binary packages that
contain different contents as a result.

We believe that the bug you reported is fixed in the latest version of
gwaei, which is due to be installed in the Debian FTP archive.

A summary of the changes between this version and the previous one is
attached.

Thank you for reporting the bug, which will now be closed.  If you
have further comments please address them to 1020670@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Andreas Tille <tille@debian.org> (supplier of updated gwaei package)

(This message was generated automatically at their request; if you
believe that there is a problem with it please contact the archive
administrators by mailing ftpmaster@ftp-master.debian.org)
Format: 1.8
Date: Thu, 27 Aug 2026 14:26:52 +0200
Source: gwaei
Architecture: source
Version: 3.6.2-10
Distribution: unstable
Urgency: medium
Maintainer: Debian QA Group <packages@qa.debian.org>
Changed-By: Andreas Tille <tille@debian.org>
Closes: 1020670 1045028 1049714 1119440 1133349 1134268
Changes:
 gwaei (3.6.2-10) unstable; urgency=medium
 .
   [ Andreas Tille ]
   * QA upload.
   * Orphan package
     Closes: #1133349
   * Maintain package in Debian team on Salsa
   * Use Github repository as Homepage
     Closes: #1134268
   * Fix clean target
     Closes: #1045028
   * Bump debhelper from old 10 to 13.
   * Remove redundant Priority: optional from source stanza.
   * Replace FSF postal address with a reference to
https://www.gnu.org/licenses/.
   * Set debhelper-compat version in Build-Depends.
   * Set upstream metadata fields: Bug-Database, Name (from ./configure),
     Repository-Browse.
   * Build-Depends: libncurses5-dev => libncurses-dev,
     remove libncursesw5-dev
   * d/rules:
      - Short dh (Closes: #1049714)
      - do not override CFLAGS (Closes: #1119440)
      - hardening
   * d/copyright: DEP5
   * Add d/lrc.config
   * Remove d/menu since there is a desktop file
   * d/control:
      - distinct short descriptions
      - lib in Section libs
      - No explicit Build-Depends from dpkg-dev needed
   * DEP3
   * Add watch file pointing to latest Git commit to advertise
     continued development but leave upgrading to people who know
     this program better
   * Standards-Version: 4.7.4
   * Remove unused lintian-overrides
 .
   [ Vagrant Cascadian ]
   * Add -ffile-prefix-map to CFLAGS
     Closes: #1020670
Checksums-Sha1:
 54eb3b2b4a7e10bdc0708d6cfa3c1dc62b8f5ae6 2108 gwaei_3.6.2-10.dsc
 3d6f4a2137655cd5b12bf44b94babbd3daee1efc 6008 gwaei_3.6.2-10.debian.tar.xz
 cc8c41d3268994b697ae8ca42d58f05572216430 18323 gwaei_3.6.2-10_amd64.buildinfo
Checksums-Sha256:
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 d33b9cb634c46ee03a4227ff7373288fc86cf609f9773ea6f41186b45607222d 6008 gwaei_3.6.2-10.debian.tar.xz
 ab8fb17d74b62acdc71411a9540f41fe02ac0dcd8a4cedbfb574bb5ea144ae70 18323 gwaei_3.6.2-10_amd64.buildinfo
Files:
 74be7912ae2cb04934b395068a0ef271 2108 gnome optional gwaei_3.6.2-10.dsc
 5ff9ff11e8ca704ee2c346d12d0201ad 6008 gnome optional gwaei_3.6.2-10.debian.tar.xz
 c3938ae41382f14a02a72b909cf7254c 18323 gnome optional gwaei_3.6.2-10_amd64.buildinfo
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