Add Redox Dockerfile and Travis Environment

[jackpot51]

This adds Redox to the Travis build. This is an example implementation of #43206

[rust-highfive]

r? @alexcrichton

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[aidanhs]

As noted in the referenced issue, this likely won't be merged imminently if only because we're at the builder capacity.

That said, there is a disabled folder in https://github.com/rust-lang/rust/tree/master/src/ci/docker/disabled which I could see us accepting a PR for in the meantime.

[jackpot51]

@aidanhs You could disable another platform. Might I suggest s390x-linux?

[Mark-Simulacrum]

I'm against removing anything from Tier 2 support that's there already today: "Official binary releases are provided for the platform." is the guarantee on the forge, and I think that implies that we'll continue producing those. I've heard that we expect to increase the quantity of available builders soon (though I don't know of a specific timeframe) which would allow us to add redox easily.

[jackpot51]

@Mark-Simulacrum I have resources to build this, is it possible to share them with you?

[aidanhs]

@jackpot51 previously builders have been added in an ad-hoc manner effectively up to the limit of current funding. At that point there was a realisation that a more sustainable model needs developing, which is what @aturon was talking about in the linked issue. While this was in progress, we have had to postpone other targets like #41133 and #41149 - this is a known ongoing problem!

My interpretation of what @aturon was saying in the linked issue is that new builders will arrive at some point and it would probably be more reasonable to talk about adding redox as a builder then.

Until that point, we probably want to avoid more ad-hoc changes - disabling existing builders likely falls under that category! (and, even if we did, we're so close to capacity that we may still not be comfortable with adding another builder since we're already seeing adverse effects of limited builders in other ways than just PRs on this repo).

@aturon or @alexcrichton may want to step in here or on the linked issue with any corrections to the above/other thoughts.

[aidanhs]

@jackpot51 I'm not aware of a way for us accept external resources right now, but we can certainly discuss it in the next infra team meeting since it's probably something we'd like to enable.

[alexcrichton]

@aidanhs nah I think you're spot on! We're currently exploring various methods of expanding capacity, but we haven't got something concrete just yet. Additionally yes, while we'd like to support custom hardware we don't currently have the infrastructure to do so.

[bors]

☔ The latest upstream changes (presumably #43316) made this pull request unmergeable. Please resolve the merge conflicts.

[aidanhs]

The core and infra team have made some progress talking about this, particularly for builders that just want a stdlib. We're not there yet, but it is something we're working on.

Just to double check - am I correct in thinking that "just want a stdlib" is what you're looking for here?

[jackpot51]

@aidanhs for now, that is correct

[alexcrichton]

Thanks for your patience here @jackpot51! Lots of teams have had a lot of discussion here, but the highlights here are:

• Infrastructure-wise there's a pretty big difference between "std nightlies" and "rustc nightlies". For producing the standard library it's actually a very small amount of resource investment on our end, and we can have one builder creating a whole bunch of standard libraries. For example right now the cross builder builds a number of standard libraries for various architectures.
• Investment-wise, because a standard library is pretty cheap, Mozilla, the current organization footing the bill, is willing to foot the bill for one builder doing a whole bunch of standard librararies. Basically if all you need is libstd in nightlies, we've got your back capacity-wise!
• Finally, the libs team discussed the maintenance burden with the standard library here, and sort of about the "what tier is this in" question. Our conclusions were somewhat vague, but intentionally so. We can't, at this time, provide a hard guarantee about whether we will forever be able to gate on platforms like redox building on CI (e.g. gating all changes to rust-lang/rust on the redox platform). What we can say, however, is that for the near future we're totally OK with gating on redox. If we add new features to the standard library which require bindings for redox we'll likely just stub it out returning an error, and then y'all will come along later to implement it!

So tl;dr we can merge this patch if you'd like by moving the new builder here into the existing cross builder. Does all that sound ok to you?

[jackpot51]

@alexcrichton Yes, that all sounds good to me! Do you want me to modify the PR or will you?

[alexcrichton]

@jackpot51 oh if you could take care of it that'd be great, I have a feeling you can get it done much more quickly than I can!

[jackpot51]

@alexcrichton@aidanhs I have rebased and I have added Redox to the cross build. I removed the change that makes travis build dist-x86_64-redox, but I left in the Dockerfile for future usage.

[alexcrichton]

I think this is now equivalent to the cross container, right? If not, can you edit the scripts here to use the shared scripts in the src/ci/docker/shared folder?

[jackpot51]

Do you mean src/docker/scripts?

[alexcrichton]

This folder for shared scripts.

[alexcrichton]

Oh sorry I also forgot to mention, but can this be moved to the src/ci/docker/disabled folder?

[jackpot51]

@alexcrichton it should be simpler now. Since the toolchain installation is the same, the script in cross is used by the dist-x86_64-redox dockerfile

[carols10cents]

friendly ping @alexcrichton, this looks ready for you!

[alexcrichton]

Ah sorry should have commented more prominently, bu the dist-x86_64-redox builder should move to the disabled folder

[jackpot51]

Ok, will do

[jackpot51]

@alexcrichton it is done

[alexcrichton]

@bors: r+

[alexcrichton]

@bors: r+

[bors]

📌 Commit 1cc33c0 has been approved by alexcrichton

[bors]

⌛ Testing commit 1cc33c0 with merge 69e6a7ff17a5c84e98f099832d2d5a40c2ae16e5...

[bors]

💔 Test failed - status-travis

[kennytm]

Legit. Please try to chmod a+x src/ci/docker/cross/install-x86_64-redox.sh and commit again.

[00:00:48] Step 15/32 : RUN ./install-x86_64-redox.sh
[00:00:48] ---> Running in 3ba43dab0982
[00:00:48] /bin/sh: 1: ./install-x86_64-redox.sh: Permission denied
[00:00:49] The command '/bin/sh -c ./install-x86_64-redox.sh' returned a non-zero code: 126
[00:00:49] The command has failed after 5 attempts.

[jackpot51]

Oops

[jackpot51]

@kennytm@alexcrichton That script is marked executable in git now.

[aidanhs]

@bors r=alexcrichton

[bors]

📌 Commit 727b473 has been approved by alexcrichton

[bors]

⌛ Testing commit 727b473 with merge 1b08e0f...

[bors]

☀️ Test successful - status-appveyor, status-travis
Approved by: alexcrichton
Pushing 1b08e0f to master...

[jackpot51]

🎉 🎉 🍰 🍰 🎆 🎆

[jackpot51]

@alexcrichton Redox rust-std is not present here: https://static.rust-lang.org/dist/nightly-channel.toml

Is there something I am missing?

[jackpot51]

Fixed here: #43950