Dear Maintainer,

your package depends on libeigen3-dev. The upstream released a
new major version of this mathematical library, 5.0.0. Some
basic information about new features and changes in this version
can be found here:

https://libeigen.gitlab.io/releases/5.0/

This is a major version change and may require code changes in packages
depending on eigen3. The key breaking changes include:

  - Minimum required C++ standard is now C++14
  - Changes in the build system integration
  - Some API name changes

lbfgspp FTBFS with libeigen3-dev 5.0.1. The full build log is available at:

https://debusine.debian.net/debian/developers-gladk-eigen3/artifact/3757053/

Here is the most probably relevant part of the failing build log:
    ===========================================
-- Performing Test WALL_SUPPORTED
-- Performing Test WALL_SUPPORTED - Success
CMake Error at CMakeLists.txt:41 (find_package):
  Could not find a configuration file for package "Eigen3" that is compatible
  with requested version "3.0".

  The following configuration files were considered but not accepted:

    /usr/share/eigen3/cmake/Eigen3Config.cmake, version: 5.0.1
      The version found is not compatible with the version requested.

Dear maintainers,

eigen3 5.0 (libeigen3-dev 5.0) is now in unstable, so these FTBFS bugs are
release-critical.  I am therefore raising their severity to serious.

Regards,

Anton

Hello,

Bug #1136245 in lbfgspp reported by you has been fixed in the
Git repository and is awaiting an upload. You can see the commit
message below and you can check the diff of the fix at:

https://salsa.debian.org/science-team/lbfgspp/-/commit/55a14d2a8d2318185c28ec88dd60ef0b34937eee

(this message was generated automatically)
-- 
Greetings

https://bugs.debian.org/1136245

We believe that the bug you reported is fixed in the latest version of
lbfgspp, 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 1136245@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Anton Gladky <gladk@debian.org> (supplier of updated lbfgspp 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, 15 Oct 2026 08:45:02 +0200
Source: lbfgspp
Architecture: source
Version: 0.4.0-2
Distribution: unstable
Urgency: medium
Maintainer: Debian Science Maintainers <debian-science-maintainers@lists.alioth.debian.org>
Changed-By: Anton Gladky <gladk@debian.org>
Closes: 1136245
Changes:
 lbfgspp (0.4.0-2) unstable; urgency=medium
 .
   * Team upload
   * Fix FTBFS with Eigen 5. (Closes: #1136245)
   * Add myself to Uploaders.
   * Remove redundant Priority: optional.
   * Drop ${shlibs:Depends} from arch:all package.
   * Bump debhelper compat level to 14.
   * Bump Standards-Version to 4.7.4 (no changes needed).
   * Update d/copyright.
   * Use salsa-ci debian.yml recipe, enable licenserecon.
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Files:
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 50b34556cbf72604f3ed1a60b2bf1d8a 3456 libdevel optional lbfgspp_0.4.0-2.debian.tar.xz
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Git-Tag-Info: tag=78ab67b5a61fd697c33db7c5d67f9947650d57d1 fp=bbbd45ea818ab86ff67e7285d3e17383cfa7ff06
Git-Tag-Tagger: Anton Gladky <gladk@debian.org>
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