add cmake-ar

[hmaarrfk]

Without this, it uses system /usr/bin/ar. You can't really uninstall binutils from centos. In my docker container, I just remove those files with rm to ensure I don't use them.

See builds 2 and 3 from
https://app.shippable.com/github/Archiconda/cmake-feedstock/dashboard/history

Checklist

• Used a fork of the feedstock to propose changes
• Bumped the build number (if the version is unchanged)
• Reset the build number to 0 (if the version changed)
• Re-rendered with the latest conda-smithy (Use the phrase @conda-forge-admin, please rerender in a comment in this PR for automated rerendering)
• Ensured the license file is being packaged.

[conda-forge-linter]

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

I just wanted to let you know that I linted all conda-recipes in your PR (recipe) and found it was in an excellent condition.

[hmaarrfk]

xref https://github.com/conda-forge/toolchain-feedstock/pull/53/files

[jakirkham]

Isn't there one provided with the compilers?

cc @mingwandroid

[hmaarrfk]

There is, but without this flag it uses /usr/bin/ar

or maybe it just calls ar

and binutils is installed by default in centos7
jjhelmus/conda4aarch64#4

[jakirkham]

Are there other things like this we should be setting (e.g. nm)?

[hmaarrfk]

I don't think so. I've been making PRs as I've found problems with the builds.

Ubuntu 18.04, which I'm using, isn't showing any problems with nm.

(basically aarch64/ubuntu with qemu-aarch64-static)

$ docker run -i -t archiconda/ubuntu bash                                                             
root@896ab8533aca:/# nm
bash: nm: command not found

[mingwandroid]

Hi @hmaarrfk, I'm not entirely sure what you have in place at present but I think you'd be better off building compilers here or at least fake compiler activation packages that set all these variables (they could even run yum etc to install system tools if detected as not being present).

This would keep things working in a more uniform way, from the perspective of the recipes.

I built an arm5 miniconda this way ages ago and in fact our current Linux compilers grew out of that work!

To build a miniconda from scratch (touchy you likely don't want to it need to do that now) you have two choices, build everything on a 'system' qemu setup where both host and build are aarch64 or else use a 'user' qemu with binfmt_misc. When using the latter build can be either aarch64 or amd64, but to bootstrap you'd probably need build to be amd64, otherwise you need to use the system python to run conda and conda-build until you have got as far as building python.

[hmaarrfk]

@mingwandroid with alot of help from jjhelmus, I basically have python 3.7, python 2.7 built, and python 3.6 is building now. I just invited you to join, mostly giving you the right to push jobs to shippable if you like.

I currently built python 3.6 and 3.7 without optimization. Not sure how the 96 Core CPUs they have affects things. You are free to play with them if you want to kill some time

Most of the work is done in this repo
https://github.com/Archiconda/build-tools
and a fork of conda-smithy I have enabled.

[jakirkham]

Is this PR still needed?

[hmaarrfk]

No, this has been taken care of in CMAKE_ARGS.

Man i can't believe this is 2 years ago now....

[hmaarrfk]

Wait 3.