Loadable lints

[kmcallister]

Now that we have loadable syntax extensions, what about loadable lints? My main interest is application-specific safety checking, either to make unsafe code safer, or to provide guarantees above and beyond Rust's memory safety.

Some example use cases:

• enforcing correct usage of Servo's JS-managed pointers
• detecting common misuses of a library, e.g. expensive or non-idiomatic constructs
• in cryptographic code, annotating which variables contain secrets and then forbidding their use in variable-time operations or memory addressing

[mcpherrinm]

I am interested in working on this. I will post an RFC soon.

[lilyball]

I really want this. rust-lua needs a loadable lint in order to get rid of all the unsafe (because of longjmp).

[kmcallister]

This is rust-lang/rfcs#89.

[kmcallister]

I have a working quick-and-dirty prototype. There are various issues to resolve before it can be merged.

[kmcallister]

This is done! See #15024.