A simple mpi program like:
```
 int me, nranks;
  MPI_Comm_rank(MPI_COMM_WORLD, &me);
  MPI_Comm_size(MPI_COMM_WORLD, &nranks);

  for (int i=0; i<nranks; i++) {
    if (me == i)
      std::cout << "hello from rank: " << me << std::endl;
    MPI_Barrier(MPI_COMM_WORLD);
  }
```

fails to run on s390x

Reproducible: Always