This package fails to build on big-endian architectures, notably s390x.

There's a fix available upstream:
https://github.com/intel/isa-l/commit/d3cfb2fb772e375cf2007e484e0a6ec0c6a7c993

Here's a debdiff that incorporates the upstream patch.

We believe that the bug you reported is fixed in the latest version of
libisal, 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 1012262@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Thomas Goirand <zigo@debian.org> (supplier of updated libisal 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, 02 Jun 2022 17:13:56 +0200
Source: libisal
Architecture: source
Version: 2.30.0-5
Distribution: unstable
Urgency: medium
Maintainer: Debian OpenStack <team+openstack@tracker.debian.org>
Changed-By: Thomas Goirand <zigo@debian.org>
Closes: 1012262
Changes:
 libisal (2.30.0-5) unstable; urgency=medium
 .
   [ Simon Chopin ]
   * d/p/s390x-compat.patch: fix the build on s390x and other big-endian
     architectures. (Closes: #1012262, LP: #1976622)
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