compiler-explorer VS rustc_codegen_gcc

I have, it's called Visual Studio Code and I ditched my old native editor(s) for it.

I'd even suggest that the fact that it's JS based has significantly changed the tech world because the editor itself will run in a browser so it's here https://godbolt.org/ , and here https://codesandbox.io, and here https://www.postman.com/, and here https://aws.amazon.com/pm/cloud9/ and 100s or 1000s of other sites.

I'm told the story of Godbolt[0] is similar.

I think that he has an ID here, so we could probably ask him. It's a very good tool.

[0] https://godbolt.org

The GodBolt compiler explorer is also useful for comparing the assembly function code between C++ and Rust.

Using several operations as examples, let's see what assembler the compiler can get. We're using the latest Clang for the x86-64 platform available on Compiler Explorer.

it is also pretty good at decompiling - try feeding the output of https://godbolt.org/ back to an LLM

As a very first step, you may start playing with https://godbolt.org/ to see how code is translated into lower-level instructions.

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.

Also, there are indeed ABI issues, e.g. for 128-bit integers and NaN.

I'm excited about both the backend & the frontend.