Richard Matthew Stallman tell people to say GNU/Linux to spread free software, but Rust programming language ecosystem is growing fastly, Rust focuses on memory safety. If one day, Rusty alternative of GNU software is published, but they're not developed by GNU project, someone may say "rust-lang/Linux" instead of "GNU/Linux", which is very bad for spreading free software. So I suggest GNU project use Rust to rewrite all GNU software to prevent future people from saying "rust-lang/Linux" instead of "GNU/Linux", because Rust language users may only support memory safety, but not free software movement. In conclusion: At least glibc and bash need to be rewritten in Rust, glibc is the interface of user-space programs and kernel syscall, I think it's better to write librust instead of glibc, preventing future people from saying "rust-lang/Linux" that may not support free software movement, since rust-lang/Linux doesn't mention GNU and only supports memory safety. And finally, Rust focuses on memory safety, it's currently safer than C++.