WIP: Do not merge: A potential recipe for handing VC versions.

[pelson]

So, here are some improvements to the way we manage the vc problem for Windows.

Ping @msarahan as there are some important implications here.

Things to note / answer:

• - The build component could be handled by conda-build automatically based on the current vc version being used, or alternatively by having yet another special environment variable.
• - conda-build-all knows about vc and expands the build matrix to use it and expose as a VC_VERSION environment variable
• - the only reason I'm using features here at all is to give the distributions unique filenames. I want extensibility of the build-string so that I don't have to re-invent the wheel (@msarahan - you may have missed this subtlety in https://github.com/conda/conda-build/pull/747/files#diff-c86934c27c2f25579540ddb447fa45bdR584 with all of the other noise). As soon as I have that, features have no place in this recipe.

[conda-forge-linter]

Hi! This is the friendly automated conda-forge-linting service.

I wanted to let you know that I linted all conda-recipes in your PR (recipe) and found some lint.

Here's what I've got...

For recipe:

• Failed to even lint the recipe (might be a conda-smithy bug) 😢

[jakirkham]

I'm guessing this should also be pinned.

[pelson]

I'm not sure actually - the vc package doesn't contain anything, and I'm not sure it even influences any package resolution. Maybe it does need to be pinned though in order to control the dependencies being installed.

[msarahan]

This is a very interesting proposal. I like it. I think it could get shorter over time, but this is a very good start. I kept asking myself "but where's Python?" - and of course, it doesn't need to be there. Thanks for pushing this forward.

[isuruf]

You can use the mpir package (https://github.com/conda-forge/mpir-feedstock) for windows build. MPIR is a fork of GMP and can be built on windows. API is the same except for some long vs long long differences.

[jakirkham]

Probably won't worry about it in this PR as this is aimed to try out the vc package with a matrix, but it is definitely something worth keeping in mind.

[jakirkham]

Put this idea in an issue ( #11 ) so we can better track and address it.

[pelson]

xref: conda-forge/tk-feedstock#2

[jakirkham]

Another solution to this problem is in PR ( conda-forge/tk-feedstock#20 ). The same thing could easily be ported here.

[isuruf]

Obsolete now that conda-build=3 can be used.