Add emulated osx-arm64 by default

[maurosilber]

Your question:

While we wait for #1781, could we add emulated builds for osx-arm64 by default?

Recently, I tried to install a package and was surprised that it wasn't available in conda-forge. But it was, only it was not compiled for osx-arm64. Given that it's been 5 years since Macs switched to ARM, and some users might not know how to modify a recipe to add support for their platform, I think it would be useful to add emulated osx-arm64 builds by default.

[mfansler]

Conda Forge currently only has a cross-compiling option for osx-arm64. If there is a specific emulation option in mind, please identify it.

Otherwise, cross-compiling is frequently not straightforward for many packages, so having it enabled on staged-recipes could significantly slow throughput. Another point of concern is that incoming recipes often have dependencies on existing feedstocks, so the conversation might be better started with a discussion about converting the "on-demand" migration into an automated one.

[maurosilber]

Yes, I meant cross-compiling for osx-arm64 from osx-64.

Can Conda-Forge try to cross-compile new recipes for osx-arm64 by default but disable and accept the recipe anyways if only that platform fails?

[mfansler]

Yes, but the automated migration would come first. In the transition, new feedstocks would also get a migration when they are compatible.