Miri maintainer note: this is a fun project, but not something we currently intend to support officially. To keep maintenance manageable, Miri only supports running on platforms that rustc supports running on.

Compiling the whole Rustc to WASM is a pretty big undertaking for many reasons.

However, Miri doesn't need an actual codegen and many other parts of the whole Rustc, so I wonder how realistic it would be to compile it and the pieces it depends on to WASM instead? Are there any obvious blockers?

Mostly opening this to gauge interest and estimate complexity, as I believe there is an interest in running Rust directly in the browser on playground-like websites.

P.S. Despite what I said in the first sentence, this was actually done for Clang a while ago - https://tbfleming.github.io/cib/ - which includes LLVM compiled to WASM that, in turn, generates more WASM dynamically during runtime. In theory, it should be possible to do the same for Rust, especially since they share LLVM, but for now having just an interpreter could already be an interesting starting goal.