Build aarch64-apple-ios-sim as part of the full macOS build

[badboy]

Part of the MCP 428 to promote this target to Tier 2.

This adds the aarch64-apple-ios-sim target as a tier 2 target, currently cross-compiled from our x86_64 apple builders. The compiler team has approved the addition per the MCP noted above, and the infrastructure team has not raised concerns with this addition at this time (as the CI time impact is expected to be minimal; this is only building std).

[rust-highfive]

r? @Mark-Simulacrum

(rust-highfive has picked a reviewer for you, use r? to override)

[Mark-Simulacrum]

Would you be up for copying this config to a try builder -- likely adding onto here:

rust/src/ci/github-actions/ci.yml

Lines 643 to 652 in 9f75dbf

	try:
	<<: *base-ci-job
	name: try
	env:
	<<: [*shared-ci-variables, *prod-variables]
	if: github.event_name == 'push' && (github.ref == 'refs/heads/try' || github.ref == 'refs/heads/try-perf') && github.repository == 'rust-lang-ci/rust'
	strategy:
	matrix:
	include:
	- *dist-x86_64-linux

?

That way we can test this out without actually landing it and make sure it builds (and hopefully someone can verify the artifacts).

[Mark-Simulacrum]

@bors try

[bors]

⌛ Trying commit 82ec1fb10f172297a8859a2a91bf865a705fdb84 with merge ab06beff0b87a039398867d10c9e6570a1d5efc4...

[bors]

☀️ Try build successful - checks-actions
Build commit: ab06beff0b87a039398867d10c9e6570a1d5efc4 (ab06beff0b87a039398867d10c9e6570a1d5efc4)

[badboy]

At the very least it built something by the right name:

-rw-r--r--   1 runner  staff    16M May 30 14:57 rust-std-nightly-aarch64-apple-ios-sim.tar.xz

How would I get that artifact from S3?

[badboy]

Ah, thanks to rustup-toolchain-installer I got it. Though as there is not rustc itself one can't just install it.
But I can check the file contents and use them against a nightly to see if that works

[badboy]

Building that commit locally (and some hackery due to the explicit version check within rustc) the artifact at https://ci-artifacts.rust-lang.org/rustc-builds/ab06beff0b87a039398867d10c9e6570a1d5efc4/rust-std-nightly-aarch64-apple-ios-sim.tar.xz seems to work.

I'll try using it tomorrow at work and see if I can get ahold a x86_64 Mac to test the full build from the try run.

[badboy]

I threw the try build from that commit onto an x86_64 macOS machine using GitHub Actions here: https://github.com/badboy/gha-macos-rust-tests/runs/2710468159

It compiles a minimal Rust library to a static library.
The outcome is what I expect, including the right version commands:

cmd LC_BUILD_VERSION
platform 7

I did not test that in the simulator itself, but I think this works exactly as planned.

[badboy]

What are the next steps here, @Mark-Simulacrum?
Obviously I need to remove the try commit, but are there other blockers like getting a decision on the overall MCP first or is having this built for the Tier 3 target ok?

[Mark-Simulacrum]

I think dropping the try part of this and updating the docs (platform support) to make this PR be the "make it tier 2" PR makes sense. I left a comment on the Zulip thread as well.

[Mark-Simulacrum]

Going to mark this as waiting-on-team; specifically a second on the MCP - rust-lang/compiler-team#428.

[apiraino]

@rustbot label +T-compiler

(hope it's correct)

[apiraino]

@Mark-Simulacrum rust-lang/compiler-team#428 has been seconded, can S-waiting-on-team be lifted here or are there further pending actions?

[apiraino]

I think we can now remove the "waiting on team" label

@rustbot label -S-waiting-on-team

[badboy]

rust-lang/compiler-team#428 has been accepted, I removed the test commit and force-pushed here.

[badboy]

Once this is landed and we verified that the produced artifacts work I can change the documentation.

[badboy]

Bump! @Mark-Simulacrum, as you gave feedback here earlier. Can we land this?

[Mark-Simulacrum]

Marked as waiting on review - I expect the answer is roughly "yes" but I'll need to take a look. Likely within the next week.

[badboy]

Thanks!

[Mark-Simulacrum]

@bors r+

[bors]

📌 Commit 61640f2 has been approved by Mark-Simulacrum

[bors]

⌛ Testing commit 61640f2 with merge a0a6bab...

[bors]

☀️ Test successful - checks-actions
Approved by: Mark-Simulacrum
Pushing a0a6bab to master...