I am building OpenMPI v2.x-dev-187-g8516895. I now see
/home/eschnett/datura/software/src/openmpi-v2.x-dev-187-g8516895/src/openmpi-v2.x-dev-187-g8516895/ompi/mca/fs/lustre/fs_lustre_file_open.c:48:5: error: use of undeclared identifier 'LOV_MAX_STRIPE_COUNT'
on several systems (e.g. Hopper at NERSC). These errors were not present in earlier snapshots.