Spack stacks drop invalid dependencies applied to packages by a
spec_list matrix operation
Without this fix, Spack would raise an error if orthogonal dependency
constraints and non-dependency constraints were applied to the same
package by a matrix and the dependency constraint was invalid for
that package. This is an error, fixed by this PR.
An example failing configuration:
spack:
definitions:
- packages: [libelf, hdf5+mpi]
- compilers: ['%gcc']
- mpis: [^openmpi]
specs:
- matrix:
- $packages
- $compilers
- $mpis
36fbd6cf4c