lp-solve fails to cross build from source for multiple reason. Number
one is that debian/rules does not tell the upstream builds scripts about
what architecture we are building for in any way. The upstream build
scripts also provide no way of picking up this information and just hard
code the build architecture compiler. They also run a test program to
determine whether we're on a 64bit or 32bit system. I'm attaching a
patch to address all of these aspects. A significant portion of it
likely should go upstream and generally helps with cross building also
on other distributions such as Yocto or PtxDist.

Helmut

We believe that the bug you reported is fixed in the latest version of
lp-solve, 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 1078930@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Rene Engelhard <rene@debian.org> (supplier of updated lp-solve 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: Mon, 11 Aug 2025 20:53:25 +0200
Source: lp-solve
Architecture: source
Version: 5.5.2.14-2
Distribution: experimental
Urgency: medium
Maintainer: Juan Esteban Monsalve Tobon <esteban@v7w.com>
Changed-By: Rene Engelhard <rene@debian.org>
Closes: 1078930
Changes:
 lp-solve (5.5.2.14-2) experimental; urgency=medium
 .
   * add patch from Helmut Grohne to Fix FTCBFS: (Closes: #1078930)
     + Pass a host compiler to the compilation scripts.
     + Rewrite platform check as compile-only test.
     + Do not fail removal of temporary files that may be missing.
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