Since macOS doesn't ship with OpenMPI (they remove it from the version of Clang they include) we'd rather not use it here because we expect a decent share of our users to be on Macs. This de-parallelizes the parts of the code that had been using OpenMPI and leaves behind some notes to guide future work re-implementing the parallelism.
As a side bonus, all new-ish versions of GCC should now also work, and the specific GCC version reference in the Makefile has been removed.
Since macOS doesn't ship with OpenMPI (they remove it from the version of Clang they include) we'd rather not use it here because we expect a decent share of our users to be on Macs. This de-parallelizes the parts of the code that had been using OpenMPI and leaves behind some notes to guide future work re-implementing the parallelism.
As a side bonus, all new-ish versions of GCC should now also work, and the specific GCC version reference in the Makefile has been removed.