cppmm VS rustc_codegen_cranelift

This seems to miss `cppmm` (C++--)[1].

This crate is currently mainly aimed at helping people from the Rust group of the Academy Software Foundation (ASWF) to make wrappers for the visual effects ecosystem of libs.[2]

It is nevertheless very useful for all types of other cases.

[1] https://github.com/vfx-rs/cppmm

[2] The above just means effort is prioritized regarding the blockers these libs present due to the resp. C++ features they use.

For now, they seem to be working on their own version of cxx and bindings for OpenEXR.

It is called C++-- [1].

At this time we only target the VFX C++ ecosystem but I'd be surprised if people wouldn't use (and extend) this to cover a broader set of C++ libs.

Maybe you can give an example of an C++ API that you deem not "translatable to C"?

[1] https://github.com/vfx-rs/cppmm

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/...