ERROR with Building LAMMPS with pair_allegro in Mac with arm64 Architecture

[ddhabal]

Hello everyone,
I am having hard time building lammps with pair_allegro on my Macbook with M2 processor and arm64 architecture. It would be nice if anyone could help me with this. I was able to successfully install proper version of Nequip, Allegro on my macbook. While building lammps, there was no issue till cmake. But in the last step with "make -j 8", I see the following error.

**[ 98%] Built target lammps
[ 98%] Building CXX object CMakeFiles/lmp.dir/Users/ddhabal/Ddhabal/cas_project/nequip/lammps/src/main.cpp.o
[100%] Linking CXX executable lmp
Undefined symbols for architecture arm64:

"long* at::TensorBase::mutable_data_ptr() const", referenced from:
at::TensorAccessor<long, 2ul, at::DefaultPtrTraits, long long> at::TensorBase::accessor<long, 2ul>() const & in liblammps.a(pair_allegro.cpp.o)
at::TensorAccessor<long, 1ul, at::DefaultPtrTraits, long long> at::TensorBase::accessor<long, 1ul>() const & in liblammps.a(pair_allegro.cpp.o)
ld: symbol(s) not found for architecture arm64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make[2]: *** [lmp] Error 1
make[1]: *** [CMakeFiles/lmp.dir/all] Error 2
make: *** [all] Error 2**

We tried building it with "libtorch", changing different version of pytorch, changing compilers but nothing seems to work. I was wondering if anyone faced this error anytime. Any help from you would be highly appreciated.

With regards
Debdas

[anjohan]

Hi Debdas,

This is going to be an exercise in having the "correct" libtorch, and I have no experience with macs. This issue looks relevant, which mentions a solution through conda: pytorch/pytorch#143571. See also

Note that this will probably not work with Kokkos, as that requires the CXX11 ABI version. In the near future, that will be available from pip and/or conda, but I think the versions currently available there will require you to build without Kokkos. Though I guess Kokkos doesn't understand Mac "GPUs" anyways and may not help.

• Anders