Hi!

While rebuilding the python related packages against the Python 3.15
version we found that iisignature fails to build on arm64:
https://debusine.debian.net/debian/r-python-python3.15/artifact/4853512/

Looking at the buildd dashboard that seems to be the case for all non
amd64/i386 architectures:
https://buildd.debian.org/status/package.php?p=iisignature

There are a 7 tests that fail, all with this error:
======================================================================
ERROR: testConsistency (tests.test_sig.A.testConsistency)
----------------------------------------------------------------------
Traceback (most recent call last):
   File
"/build/reproducible-path/iisignature-0.23+git20260603.447577b+ds/.pybuild/cpython3_3.14_iisignature/build/tests/test_sig.py",
line 322, in testConsistency
     self.consistency(False, 3, 6)
     ~~~~~~~~~~~~~~~~^^^^^^^^^^^^^
   File
"/build/reproducible-path/iisignature-0.23+git20260603.447577b+ds/.pybuild/cpython3_3.14_iisignature/build/tests/test_sig.py",
line 258, in consistency
     s = prepare(dim, level, "coshx" if coropa else "cosx")
   File
"/build/reproducible-path/iisignature-0.23+git20260603.447577b+ds/.pybuild/cpython3_3.14_iisignature/build/tests/test_sig.py",
line 18, in prepare
     return iisignature.prepare(d, m, "".join(methodfilter(methods)))
            ~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
RuntimeError: Cannot use the 'C' (compiled) method with this CPU
architecture
======================================================================

Please consider either fixing the code so that it works correctly on
other architectures, or if you think that's not possible, explicitly
declaring that it only works on amd64 and i386.

We believe that the bug you reported is fixed in the latest version of
iisignature, 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 1149530@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Pierre Gruet <pgt@debian.org> (supplier of updated iisignature 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: Wed, 30 Sep 2026 16:20:22 +0200
Source: iisignature
Architecture: source
Version: 0.23+git20260603.447577b+ds-2
Distribution: unstable
Urgency: medium
Maintainer: Debian Math Team <team+math@tracker.debian.org>
Changed-By: Pierre Gruet <pgt@debian.org>
Closes: 1149530
Changes:
 iisignature (0.23+git20260603.447577b+ds-2) unstable; urgency=medium
 .
   * Building the binary package only on amd64 and i386 (Closes: #1149530)
Checksums-Sha1:
 bf72ea3b52852e151bb3b776ffe0e4fc7139e907 2217 iisignature_0.23+git20260603.447577b+ds-2.dsc
 df8288699a2654cc390fdc678f88b894e5414789 2516 iisignature_0.23+git20260603.447577b+ds-2.debian.tar.xz
 87ff75b8016ad85c968ad24899bd0e65b0360662 7429 iisignature_0.23+git20260603.447577b+ds-2_amd64.buildinfo
Checksums-Sha256:
 c1cf45562f05d461a587a7643ff90824f314a44c6d29247cfe0c13298a47d93f 2217 iisignature_0.23+git20260603.447577b+ds-2.dsc
 8de9887fe852b6b32f15331b9ef9aff4fb0d1cd4b06f0aaa497b2533e43023c9 2516 iisignature_0.23+git20260603.447577b+ds-2.debian.tar.xz
 25e2015ffc0221942eba8739ea8235e5273932183069f6242e55b7e02adc3490 7429 iisignature_0.23+git20260603.447577b+ds-2_amd64.buildinfo
Files:
 76619df0741ada1fd5e6fad985cda4ee 2217 math optional iisignature_0.23+git20260603.447577b+ds-2.dsc
 32692f1383dce5678b6d5d70e2a95d1d 2516 math optional iisignature_0.23+git20260603.447577b+ds-2.debian.tar.xz
 b53fd07dec3056297bda1a9ea3ce8d6e 7429 math optional iisignature_0.23+git20260603.447577b+ds-2_amd64.buildinfo
-----BEGIN PGP SIGNATURE-----
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=eysg
-----END PGP SIGNATURE-----