Dear maintainer,

Upstream dev makes a number of assumption on the filesystem layout,
that cause failure on Debian systems.
In practice it means that the cmake files can't be used when
the library is installed in multiarch dirs.

A simple
   find_package(c4core REQUIRED)

would fail with:
   CMake Error at /usr/lib/x86_64-linux-gnu/cmake/c4core/c4coreConfig.cmake:14 (message):
     File or directory /usr/lib/include/ referenced by variable
     C4CORE_INCLUDE_DIR does not exist !


One "hack"/simple-solution is to tweak the upstream's assumption
with a simple patch like the one in attachement

The same problem will exist in src:rapidyaml when upgraded,
as it use the same "c4Project.cmake" file from the same upstream

Cheers,
Sébastien -- waiting for to dust to settle to upgrade another piece
              of software that depends on src:rapidyaml

We believe that the bug you reported is fixed in the latest version of
c4core, 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 1146292@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Sébastien Noel <twolife@debian.org> (supplier of updated c4core 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, 31 Aug 2026 14:53:53 +0200
Source: c4core
Architecture: source
Version: 0.6.0-4
Distribution: unstable
Urgency: medium
Maintainer: Gabriel Barrantes <gabriel.barrantes.dev@outlook.com>
Changed-By: Sébastien Noel <twolife@debian.org>
Closes: 1146292
Changes:
 c4core (0.6.0-4) unstable; urgency=medium
 .
   * Team upload
   * Fix CMake files (Closes: #1146292)
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