MGP without KOKKOS

[dft4py]

Describe the bug Is it possible to compile the MGP plugin without KOKKOS?

To Reproduce Starting from a clean Ubuntu installation, I download LAAMPS from the github, move the mgp files to the /src/ directory of lamps and run cmake.

First I get an error about pair_mgp_kokkos not being able to find pair_kokkos.h, which makes sense since I have not installed KOKKOS. If I remove this file then the installation proceeds normally again but when the mgp_pair.cpp file tries to compile I get an error about a protected member.

pair.mgp.cpp:934:33: error "int LAMMPS_NS::NeighREquest::half" is protected within this context

[anjohan]

Hi,

Your final error comes from a change in the LAMMPS neighbor API that we haven't incorporated yet. For the time being, you can use a slightly older version, e.g. the git tag stable_29Sep2021_update2.