[Experiment] set .cargo/registry/src as readonly

[weihanglo]

Need a crater run on check mode to see how readonly registry sources break stuff.

This does not take into account the case which I mentioned earlier, so failure cases may be far less than expected. I will appreciate if anyone gives a hint about how to make crater run cargo c && rm -rf ~/.cargo/registry/src && cargo c :)

Still, changing the permission bits causes build.rs not able to run some executables¹, or makes .cargo-ok not able to write². So, let's see how far it goes.

r? @ghost

Footnotes

1. https://github.com/rust-lang/cargo/pull/9131 ↩

2. https://github.com/rust-lang/cargo/blob/c9d8c28cba959c347271eaf31c9abfbb74c690bd/src/cargo/sources/registry/mod.rs#L657-L664 ↩

[weihanglo]

@bors try

[bors]

⌛ Trying commit cd01cbd8c49aec8aca4ef6012727cb2d670de09e with merge 665f4256561629ddbc1123adf44c84e656ad9db0...

[bors]

💔 Test failed - checks-actions

[weihanglo]

@bors try

[bors]

⌛ Trying commit c012e6c26e60d903253621afabca19e1b1f5a87a with merge 56723e30e40b52b73b9722d31caeec71c84a0ed4...

[jyn514]

This does not take into account the case which I mentioned earlier, so failure cases may be far less than expected. I will appreciate if anyone gives a hint about how to make crater run cargo c && rm -rf ~/.cargo/registry/src && cargo c :)

I don't think there's an existing way to do this: https://github.com/rust-lang/crater/blob/master/docs/bot-usage.md#available-experiment-modes.
If you're ok just running cargo check, you can use mode=check-only. Otherwise you'll have to add a new mode to crater itself, here's an example: rust-lang/crater#543

[bors]

☀️ Try build successful - checks-actions
Build commit: 56723e30e40b52b73b9722d31caeec71c84a0ed4 (56723e30e40b52b73b9722d31caeec71c84a0ed4)

[weihanglo]

Thanks for the info! I am fine with check-only mode first. Let me check if I get the permission.

@craterbot run mode=check-only crates=top-100

[craterbot]

🔒 Error: you're not allowed to interact with this bot.

🔑 If you are a member of the Rust team and need access, add yourself to the whitelist.
ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

[weihanglo]

Okay, no 😞
@jyn514 could you help run crater? Thanks!

[jyn514]

@craterbot run mode=check-only crates=top-100

[craterbot]

👌 Experiment pr-98370 created and queued.
🤖 Automatically detected try build 56723e30e40b52b73b9722d31caeec71c84a0ed4
🔍 You can check out the queue and this experiment's details.

ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

[jyn514]

@craterbot cancel

@craterbot run mode=check-only crates=top-100 p=1 (this is fast to run, no need to wait a week)

[craterbot]

🚨 Error: failed to parse the command

🆘 If you have any trouble with Crater please ping @rust-lang/infra!
ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

[jyn514]

@craterbot abort name=pr-98370

@craterbot run mode=check-only crates=top-100 p=1 (this is fast to run, no need to wait a week)

[craterbot]

🗑️ Experiment pr-98370 deleted!

ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

[jyn514]

@craterbot run mode=check-only crates=top-100 p=1 (this is fast to run, no need to wait a week)

[craterbot]

🚨 Error: failed to parse the command

🆘 If you have any trouble with Crater please ping @rust-lang/infra!
ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

[craterbot]

👌 Experiment pr-98370 created and queued.
🤖 Automatically detected try build 56723e30e40b52b73b9722d31caeec71c84a0ed4
🔍 You can check out the queue and this experiment's details.

ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

[craterbot]

🚧 Experiment pr-98370 is now running

ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

[craterbot]

🎉 Experiment pr-98370 is completed!
📊 0 regressed and 0 fixed (100 total)
📰 Open the full report.

⚠️ If you notice any spurious failure please add them to the blacklist!
ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

[ehuss]

I will appreciate if anyone gives a hint about how to make crater run cargo c && rm -rf ~/.cargo/registry/src && cargo c :)

I haven't had a chance to look at this, but I just wanted to quickly mention that you can implement whatever logic you want inside your cargo fork. Like in commands/check.rs you can call fs::remove_dir_all(…).

ehuss/cargo@e96bdb0...6901690 is an example of how I did something similar. It has an environment variable so that the "outer" cargo check would run the logic, and the "inner" cargo (with the environment variable set) would run like normal.

Also, I also wanted to mention that I think crater prefetches all dependencies, so this may not work as expected. Sorry, I forgot about that when we were discussing this earlier. I'm also not certain how CARGO_HOME gets mounted in the docker container, and whether or not you can actually modify CARGO_HOME. (Sorry, I have forgotten a lot of how rustwide works.)

Also, just looking at the diff, it looks like the src/tools/cargo submodule may not be at the correct hash. It looks like this has 85e457e158db216a2938d51bc3b617a5a7fe6015, but your branch is at 850d7ce755ad62d9db436ec2697b879d568ce16d. At least, I don't see your changes in this diff.

[weihanglo]

Oops. My fault. Thanks for the tip ehuss. Updated here weihanglo/cargo@fa889b3

@bors try

[bors]

⌛ Trying commit d0371b8 with merge caa9a0ab7f12e74ec4868e297b789e6c6860d50a...

[bors]

☀️ Try build successful - checks-actions
Build commit: caa9a0ab7f12e74ec4868e297b789e6c6860d50a (caa9a0ab7f12e74ec4868e297b789e6c6860d50a)

[weihanglo]

Me again. @jyn514 could you help run the same crater command again please 🙏🏾
Thank you!

[jyn514]

@craterbot run mode=check-only crates=top-100 p=1

[craterbot]

👌 Experiment pr-98370-1 created and queued.
🤖 Automatically detected try build caa9a0ab7f12e74ec4868e297b789e6c6860d50a
🔍 You can check out the queue and this experiment's details.

ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

[craterbot]

🚧 Experiment pr-98370-1 is now running

ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

[craterbot]

🎉 Experiment pr-98370-1 is completed!
📊 82 regressed and 0 fixed (100 total)
📰 Open the full report.

⚠️ If you notice any spurious failure please add them to the blacklist!
ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

[jyn514]

Looks like @ehuss was right:

[INFO] [stderr] >> 1st remove `/opt/rustwide/cargo-home/registry/src`
[INFO] [stderr] error: Read-only file system (os error 30)

On the bright side I think this means that anything Crater is compiling isn't writing to the registry?

[Mark-Simulacrum]

On the bright side I think this means that anything Crater is compiling isn't writing to the registry?

I would rephrase this to any successful compilation in Crater won't be writing to the registry. You can probably download a full-run's results e.g., https://crater-reports.s3.amazonaws.com/pr-99217/logs-archives/all.tar.gz and grep those logs for Read-only filesystem to try to get an idea of the percentage of crates we fail to run due to this issue (at least at cargo check time).

[weihanglo]

Going to close this now. Will revisit if I have more time on it.