Known Issues

This is a list of known bugs in Spack. It provides ways of getting around these problems if you encounter them.

Default variants are not taken into account during concretization

Status: Expected to be fixed in the next release

Current concretization algorithm does not take into account default values of variants when adding extra constraints to the spec via CLI. For example you may encounter the following error when trying to specify which MPI provider to use:

$ spack install hdf5 ^openmpi
==> Error: hdf5 does not depend on openmpi

although the hdf5 package contains:

variant('mpi', default=True, description='Enable MPI support')
depends_on('mpi', when='+mpi')

A workaround is to explicitly activate the variant related to the dependency:

$ spack install hdf5+mpi ^openmpi

See for further details.

spack extensions doesn’t work

Status: Up for grabs if you want to try to fix it

Spack provides an extensions command that lists all available extensions of a package, the ones that are installed, and the ones that are already activated. This is very useful in conjunction with spack activate. Unfortunately, this command no longer works:

$ spack extensions python
==> python@2.7.13%clang@8.0.0-apple~tk~ucs4 arch=darwin-sierra-x86_64 -ckrr4mg has no extensions.

See for further details.

spack setup doesn’t work

Status: Work in progress

Spack provides a setup command that is useful for the development of software outside of Spack. Unfortunately, this command no longer works. See and for details. This is expected to be fixed by