[firedrake] openMPI 3.0 testing issues

Hi, I am trying to fix my firedrake install. I appear to be failing all of the parallel tests (200 or so). I have narrowed the problem down to the way pytest is calling MPI and have a minimal failing example: from subprocess import check_call from mpi4py import MPI call = ["mpiexec", "-n", "1", "hostname"] check_call(call) comment out mpi4py line and it runs fine In anticipation of XY problem, I'm just trying to pass the firedrake tests. (this is openMPI 3.0.0 on my Arch Linux install, but verified failing on another system also) I'm not yet on the mailing list, but this is cross posted in slack. Cheers, Jack