d52 fails to cross build from source, because it uses cdbs and as a
result uses the build architecture compiler. Cross building using cdbs
isn't supported well, so I propose converting the package to debhelper.
Once doing so, it just cross builds out of the box. I'm attaching a
patch for your convenience.

Helmut

We believe that the bug you reported is fixed in the latest version of
d52, 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 1086541@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Helmut Grohne <helmut@subdivi.de> (supplier of updated d52 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: Sun, 24 Aug 2025 18:36:21 +0100
Source: d52
Architecture: source
Version: 3.4.1-1.4
Distribution: unstable
Urgency: medium
Maintainer: Uwe Hermann <uwe@debian.org>
Changed-By: Helmut Grohne <helmut@subdivi.de>
Closes: 1086541
Changes:
 d52 (3.4.1-1.4) unstable; urgency=medium
 .
   * Non-maintainer upload.
   * Fix FTCBFS: Convert to debhelper. (Closes: #1086541)
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