Rust-for-Linux VS rustc_codegen_gcc

You're welcome.

> Any concerns of the same kind of thing?

Here's the canonical list: https://github.com/Rust-for-Linux/linux/issues/2

There's a lot, and I don't know the status of many of them, personally. But I don't see anything there that I know is not gonna work out, like for example, they aren't using specialization. Most of it feels like very nuts and bolts codegen options and similar things.

That said, back in August, the Rust Project announced their goals for the second half of this year: https://blog.rust-lang.org/2024/08/12/Project-goals.html

They say that they're committed to getting this stuff done, and in particular: https://rust-lang.github.io/rust-project-goals/2024h2/rfl_st...

> Closing these issues gets us within striking distance of being able to build the RFL codebase on stable Rust.

So, things sound good, in my mind.

The goal of rust for linux isn't to wholesale translate linux into rust, but simply to be able to write pieces of linux (largely new ones) in rust. I think it's very unlikely anyone (including google) will take on a wholesale translation anytime soon. That said

> It's unlikely that Google has much sway here

Google has helped fund the rust for linux project pretty much from the start [1], they're one of three organizations mentioned on the homepage due to their sponorship [2]. They're actively involved in it, and have already ported their android "binder" driver into it with the intent to ship it in android. This strikes me as a very weird take.

[1] https://www.memorysafety.org/blog/supporting-miguel-ojeda-ru...

[2] https://rust-for-linux.com/

Rust is backwards compatible when you stick to stable features, but the kernel uses unstable features that can and do incur breaking changes.

https://github.com/Rust-for-Linux/linux/issues/2

> How would this work?

Don't know exactly what you're asking.

> And why would it be a better idea?

Poorly written device drivers are a significant attack vector. It's one of the reasons Linux is now exploring using Rust for its own device drivers.[0] You may be asking -- why Rust and not some other language? Rust has many of the performance and interoperability advantages of C and C++, but as noted, makes certain classes of memory safety issues impossible. Rust also has significant mindshare among systems programming communities.

[0]: https://rust-for-linux.com

Rust-for-Linux issue tracker

That doesn't require a whole new frontend, just a GCC backend will be enough. This is in fact already being worked on with rustc_codegen_gcc https://github.com/rust-lang/rustc_codegen_gcc

Alternatively, there's another initiative called codegen_gcc which is about using GCC as a backend for the rustc compiler. It's (much) more advanced in Rust support, but I am not sure how easy it would be to use a modified libgccjit from there.

In addition to what others have said about platform support, Rust is also on its way to gaining more platform support through rustc_codegen_gcc, the GCC codegen backend for rustc, as an alternative to the LLVM backend. That means many of the platforms GCC supports will suddenly become available with Rust.

Yeah, rustc_codegen_gcc is a GCC backend for rustc, and its making a lot of good regular progress.

gcc-rs is one of two projects for bringing Rust to gcc. gcc-rs is the more ambitious of the two, with an entirely new frontend. There is also rustc_codegen_gcc (https://github.com/rust-lang/rustc_codegen_gcc) that keeps the rustc frontend, and only swaps out LLVM for GCC at the codegen stage.

Fixing unwinding in release mode is still ungoing. I could use some help here, so anyone with some understanding of unwinding, landing pads or GCC, please come on this issue to discuss this.

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.

Good idea. I added the tag "help wanted" to the issue.