chore: support for eigen5

[beniz]

Support for eigen5, from #264

[mcdesseroit-eos]

I have an issue with this line
for eigen5 it doesn't work
can you put this line with the else() statement?

[beniz]

It works for me:

cmake -S /path/to/eigen-5.0.1 -B /path/to/eigen-5.0.1/build

and

cmake .. -DCMAKE_INSTALL_PREFIX=~/.local/ -DLIBCMAES_BUILD_TESTS=ON -DLIBCMAES_EIGEN_5=ON -DEigen3_DIR=/path/to/eigen-5.0.1/build

What exactly is your error ?

[mcdesseroit-eos]

It is because I build it directly with conan and add the requirements from our conan remote

def requirements(self):
        self.requires.add("eigen/5.0.0+0@jenkins/stable")

thus I have:

CMake Error at CMakeLists.txt:88 (find_package):

By not providing "FindEigen3.cmake" in CMAKE_MODULE_PATH this project has
asked CMake to find a package configuration file provided by "Eigen3", but
CMake did not find one.

Could not find a package configuration file provided by "Eigen3" with any
of the following names:
Eigen3Config.cmake
eigen3-config.cmake

Add the installation prefix of "Eigen3" to CMAKE_PREFIX_PATH or set
"Eigen3_DIR" to a directory containing one of the above files. If "Eigen3"
provides a separate development package or SDK, be sure it has been
installed.

[beniz]

I believe you need the cmake -S step above when not using conan, as it does create the missing Eigen3 config files.
I am not familiar with the conan path, can you provide the full set of steps to reproduce ?

[mcdesseroit-eos]

Thank you very much for your answer, I added :
cmake.definitions["Eigen3_DIR"]
in my conanfile and it worked !!!!

[beniz]

should we add it to the conan .py file ?

[mcdesseroit-eos]

for my part, I would have say no, it's not mandatory