When can we have rdylib?

[ckaran]

@isaac

I'll quote the last paragraph of my first response:

So, on the topic of a safe ABI: It's impossible to determine the total behavior of code in all circumstances, indeed, the issue is isomorphic to the halting problem (in anything other than trivial cases). The best we can do is ensure type safety and safety guarantees, reflect that in the version, and entrust conventions and requirements are fully checked at the boundary. [emphasis mine]

My bad, typed too fast, and didn't read enough.

@isaac

Although we can't verify the behavior is correct, we can at least enforce type safety and rust safety guarantees at the boundary.

I both agree and disagree with this statement. Assuming everyone is following all of the rules, then I think that this will be true. The issue that I don't think we can prove that people are following the rules from binary blobs alone, so if a bad actor slides in a new rdylib that violates the rules, we won't be able to check it. With statically linked code, the compiler has access to everything, and can therefore make more guarantees across boundaries.

[Yoric]

Another compiler/runtime that should be looked at is OCaml + DynLink. OCaml is somewhat similar to Rust, insofar as it supports parametric polymorphism and relies a lot upon inlining (and I think specialization, I don't remember).

[djc]

@scottmcm

(I do think it'd be cool to have a CLR backend for Rust, through.)

Like Llama?

https://ericsink.com/entries/llama_rust_resvg.html