Rust src

[Ludea]

I need to install rust src.
For now, I download it from rust https://forge.rust-lang.org/infra/other-installation-methods.html#source-code
It could be awesome to have a src package

EDIT: FYI, using

[unstable]
build-std-features = ["compiler-builtins-mem"]
build-std = ["core", "compiler_builtins"]

to my project, i can't build into device.
Building from x86_64 works as expected