One easy way to help out on an open source project is to check if a bug still reproduces. There's one kind of bug that's very special to Rust: the ICE. Internal Compiler Errors are especially weird, since a refactoring can sometimes fix them. And we have 200 ICEs: https://github.com/rust-lang/rust/issues?q=is%3Aopen+is%3Aissue+label%3AI-ICE
Basically, there's a src directory, with one file per ICE. A small Bash script loops over all the files, ensuring that they cause an ICE. If any of them don't, the build fails. I've set the repo up with Travis and Nightli.es, so we'll test each ICE once per day.
I've added two ICEs to start, but since this is a fairly easy way to contribute to a project, I haven't done more. If you're new to open source, please drop by and give me a hand!
Issues are often tagged with E-needstest when someone notices they seem to be fixed (and then someone else might pick half a dozen of those issues and submit a PR with their tests to close them). I suspect that this was the approach @steveklabnik was intending to take when glacier detects something is resolved.
So what's the appropriate steps to take if one finds an issue in that list that doesn't ICE anymore? (this https://github.com/rust-lang/rust/issues/27895 doesn't ICE for me on 1.4.0 beta 3)