Hi,

This is a question about how virtual dependencies work. On the develop branch, if run:

$ spack providers mpe
mpe2

... as expected.

If I then (arbitrarily) edit var/spack/packages/zlib/package.py and insert

"provides('mpe')"

(I know zlib doesn't do this)

and then run:

$ spack providers mpe
zlib

but there's now no mention of 'mpe2'.

Is this as intended? Should I be adding more detailed version information to the virtual deps?

This is just a test example -- the case I'm thinking of is that, say, blas could be provided by atlas, openblas, mkl, acml,

Darach