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

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

https://debusine.debian.net/debian/developers-gladk-eigen3/artifact/3759397/

Here is the most probably relevant part of the failing build log:
    ===========================================

We believe that the bug you reported is fixed in the latest version of
openbabel, 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 1136307@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Andrius Merkys <merkys@debian.org> (supplier of updated openbabel 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: Wed, 13 May 2026 05:07:09 -0400
Source: openbabel
Architecture: source
Version: 3.1.1+dfsg-15~exp
Distribution: experimental
Urgency: medium
Maintainer: Debichem Team <debichem-devel@lists.alioth.debian.org>
Changed-By: Andrius Merkys <merkys@debian.org>
Closes: 1136307
Changes:
 openbabel (3.1.1+dfsg-15~exp) experimental; urgency=medium
 .
   * Adapt to build with libeigen3-dev 5.0.1 (Closes: #1136307)
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