I am trying to install openmc with mpi support. every time I run the make command I get the error: /usr/include/hdf5/mpich/H5public.h:61:13: fatal error: mpi.h: No such file or directory
Make sure that you set the CC, FC, and CXX environment variables at the time you call CMake (as described here). I think what’s happening here is that it’s trying to use a non-MPI-wrapper version of the C++ compiler, so it’s not able to find an MPI header file.
Best,
Paul