Genuine question: How to switch codes written in 2003 to Rust?
Auto-translation won't work because Rust won't allow you to build it in the same way you would have built it in C. It requires a full up redesign of the code to follow the Rust development model.
That is not entirely true, but if you translate the C code to Rust, you get C code, in Rust, with similar issues (or possibly worse).
Of course the purpose would be to clean it up from there on, but it's unclear whether that's a better path than doing the conversion piecemeal by hand. The C2Rust people certainly seem to think so, but I don't know if there are good "client stories" about that path so far, whereas the manual approach does have some (e.g. librsvg), though it's not for the faint of heart.
thus it was basically true after all? Like, sure, Rust is turing-complete so you can simulate whatever C did and thus technically you can translate anything that C can do into Rust. But if it doesn't fix any problems, then have you really translated it into Rust?
No?
> Like, sure, Rust is turing-complete so you can simulate whatever C
It's not simulating anything, and has nothing to do with turing completeness.
> But if it doesn't fix any problems, then have you really translated it into Rust?
Yeees? Unless your definition of "translated" has nothing to do with the word or the concept.
You end up with a project full of rust code which builds using rust's toolchains. That sounds like a translation to me.
The goal definitely isn't to keep it as is, the entire point of C2Rust is to provide a jumping point then not have to shuffle between the two as you perform the conversion.
So... carefully and slowly.
Before that I've never heard of projects which successfully did C to Rust transition, keeping its C API intact and could be used as a drop-in replacement. Glad to hear that there are already some success stories.