BEAMS3D and MPI_CHECK behavior

[lazersos]

The code in question is in beams3d_runtime.f90 specifically:

#if defined(MPI_OPT)
        CALL MPI_BARRIER(MPI_COMM_BEAMS,ierr_mpi)
        ALLOCATE(error_array(1:nprocs_beams))
        ierr_mpi = 0
        CALL MPI_ALLGATHER(error_num,1,MPI_INTEGER,error_array,1,MPI_INTEGER,MPI_COMM_BEAMS,ierr_mpi)
        ierr_mpi = 0
        CALL MPI_BARRIER(MPI_COMM_BEAMS,ierr_mpi)
        IF (ANY(error_array .ne. 0)) CALL MPI_FINALIZE(ierr_mpi)
        DEALLOCATE(error_array)
        RETURN
#else
        IF (error_num .eq. MPI_CHECK) RETURN
#endif

So this makes no sense to me. I believe what I intended to do is have create an array of errors, then if any one process had and error, perform an MPI_FINALIZE and otherwise return control to the code. Now there are two issues with this.

1. This will not do that.
2. Unless error_array is being defaulted to 0, there is a good chance this will cause the code to crash.

I suspect some of the crashy behavior we've seen on Raven/Cobra is possibly due to this. The fix is rather straightforward and I will work on testing it.