From an question on answers.ros.org I noticed that we’ve ended up with semi overlapping duplicate entries for eigen.
I’ve submitted a PR to propose removing the less complete key eigen3 which only has fedora and gentoo rules. Those same rules exist using the eigen rosdep key.
Thie PR is here: remove partial duplicate eigen3 rosdep rule by tfoote · Pull Request #13200 · ros/rosdistro · GitHub please comment if this will effect you adversely. If you’re using this rule you can simply change to use the eigen key as a dependency instead of eigen3.