It's going to work for the most part. Most people know that. It's a file by file, mostly function by function, conversion from one low level language to another with a very large test suite (with lots of Rust unsafe to work around differences). I've done that for C tools and it's fine, with some obscure edge cases here and there. The challenges are going to be making the new, very ugly, alien codebase idiomatic Rust in future and adding features or debugging the complex issues. I wish the developers luck. They're in for a slog.

However, you can never prove that it hasn't gone wrong, because there are so many long-form problems with software (quiet bugs, maintainability issues, etc). This creates FUD.

Having seen some of the diffs, it's already going wrong in my view.