[3dprinter-general] Bug#1148589: FTBFS: Could not find a configuration file for Eigen3

[Gregor Riepl]

> CMake Error at CMakeLists.txt:379 (find_package):
>   Could not find a configuration file for package "Eigen3" that is compatible
>   with requested version "3.3.7".
> 
>   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.
libeigen3 was updated to version 5.0 in sid, which has some breaking changes.

Changing "find_package(Eigen3 3.3.7 REQUIRED)" to "find_package(Eigen3 3.3...5 REQUIRED)" helps getting the build process going, but there are other issues.

I tried fixing the include path by adding "target_link_libraries(<target> Eigen3::Eigen)" to all affected targets, as documented in [1] - this works mostly, except for libslic3r, which still doesn't build.

Can somebody help?

[1] https://libeigen.gitlab.io/eigen/docs-5.0/TopicCMakeGuide.html