sccache VS rustc_codegen_cranelift

Use icecream or sccache. sccache supports distributed builds.

https://github.com/mozilla/sccache/blob/main/docs/Distribute...

Worth noting that the first commit in sccache git repository was in 2014 (https://github.com/mozilla/sccache/commit/115016e0a83b290dc2...). So I suppose that what "happened" happened waay back.

If you have lots of shared dependencies, maybe try sccache?

I'm going to set up sccache [0] to use it tomorrow. We use MSVC, so EFS is off the cards.

[0] https://github.com/mozilla/sccache/blob/main/docs/S3.md

I think the primary benefit of pre-built procmacros will be for build servers which don't use a persistent cache (like sccache), since they have to compile all dependencies every time. But IMO improved support for persistent caches would be a better investment compared to adding support for pre-built procmacros.

Checkout https://github.com/mozilla/sccache

https://github.com/mozilla/sccache is another option which addresses the use cases of both icecream and ccache (and also supports Rust, and cloud storage of artifacts, if those are useful for you)

That being said a compilation cache, eg the de-facto standard for Rust: sccache (https://github.com/mozilla/sccache) will help to compile and store some of the build artifacts centralized - still for each crate version + build profile (RUSTFLAGS) combination.

Windows is supported. See https://github.com/rust-lang/rustc_codegen_cranelift/issues/....

> When this happens, it seems like it'll be possible to get the LLVM bits out of the bootstrap process and lead to a fully self-hosted Rust.

What do you mean by "when this happens"? GP's point is that this has already happened: the Cranelift backend is feature-complete from the perspective of the language [0], except for inline assembly and unwinding on panic. It was merged into the upstream compiler in 2020 [1], and a compiler built with only the Cranelift backend is perfectly capable of building another compiler. LLVM hasn't been a necessary component of the Rust compiler for quite some time.

[0] https://github.com/bjorn3/rustc_codegen_cranelift

[1] https://github.com/rust-lang/rust/pull/77975

Note that the Cranelift codegen will eventually become standard for debug builds to speed them up.

Maybe one day we'll have rustc b3 backend like what they did with Cranelift

Additionally, there is gcc codegen for rustc (https://github.com/rust-lang/rustc_codegen_gcc), which is not a compiler per se, but an alternative code generator, with more architectures supported and other nice things. It's also coming along, but there's still a lot of work to do there too. There's also Cranelift codegen (https://github.com/bjorn3/rustc_codegen_cranelift), which is designed to make debug builds faster, but this is not as exciting/useful as the other 2.

For the instant reloading, that's in Sycamore, so you should speak to its devs, but as for the alternative compiler backend, it's not my project, but it uses Cranelift and works pretty well! See https://github.com/bjorn3/rustc_codegen_cranelift for details.

The more immediate goal of "distribute the cranelift backend as a rustup component" has been making good progress and seems like it might happen relatively soon https://github.com/bjorn3/rustc_codegen_cranelift/milestone/...