Package: libeigen3-dev Version: 3.3.7-1 X-Debbugs-CC: gin...@debian.org I'm seeing this problem when attempting to build my company's ROS-based robotics software on the not-yet-released Ubuntu Focal.
Upstream had patched this issue on their master branch (targeting Eigen 3.4), and was gracious enough to cherry-pick the changes over to their 3.3 support branch, see: https://gitlab.com/libeigen/eigen/-/merge_requests/29 https://gitlab.com/libeigen/eigen/-/commits/3.3 Thanks very much to Christoph Hertzberg for the quick turnaround on that. I have in turn imported these patches as-is to the current 3.3.7-1 package and released it to PPA here: https://launchpad.net/~mikepurvis/+archive/ubuntu/eigen/ I have installed that version into my environment and confirmed that it corrects the issues with my build. I proposed that the Ubuntu maintainer take the patches, but they suggested sending them upstream to Debian: https://bugs.launchpad.net/ubuntu/+source/eigen3/+bug/1865225 Am hopeful that this can be fixed ahead of the Focal release so that we don't have to silence that new warning in all of the build configs where we use -Werror! I am using Ubuntu Focal 20.04 in a chroot with kernel 4.15.0-72-generic, and libc 5.4.0-14.17.