gistfile1.py

easyblock = "Toolchain"

name = 'foss'
version = '2015b'

homepage = '(none)'
description = """GNU Compiler Collection (GCC) based compiler toolchain, including
 OpenMPI for MPI support, OpenBLAS (BLAS and LAPACK support), FFTW and ScaLAPACK."""

toolchain = {'name': 'dummy', 'version': 'dummy'}

gccver = '5.1.0'
binutilsver = '2.25'
tcver = '%s-binutils-%s' % (gccver, binutilsver)

blaslib = 'OpenBLAS'
blasver = '0.2.14'
blas = '%s-%s' % (blaslib, blasver)
blassuff = '-LAPACK-3.5.0'

# toolchain used to build foss dependencies
comp_mpi_tc_name = 'gompi'
comp_mpi_tc_ver = "%s" % version
comp_mpi_tc = (comp_mpi_tc_name, comp_mpi_tc_ver)

# compiler toolchain depencies
# we need GCC and OpenMPI as explicit dependencies instead of gompi toolchain
# because of toolchain preperation functions
# For binutils, stick to http://wiki.osdev.org/Cross-Compiler_Successful_Builds
dependencies = [
    ('GCC', gccver, '-binutils-%s' % binutilsver),
    ('binutils', binutilsver, '', ('GCC', tcver)),
    ('OpenMPI', '1.8.5', '', ('GNU', '%s-%s' % (gccver, binutilsver))),
    (blaslib, blasver, blassuff, ('GNU', '%s-%s' % (gccver, binutilsver))),
    ('FFTW', '3.3.4', '', comp_mpi_tc),
    ('ScaLAPACK', '2.0.2', '-%s%s' % (blas, blassuff), comp_mpi_tc),
]

moduleclass = 'toolchain'

It does seem like you should base this on openmpi 1.8.6, even though it is pre-release, there is a release candidate now.