cargo fix won't fix double-error of crate renamed to reserved identier

[cramertj]

This is particularly pathological and might be to the point of "wontfix", but in fuchsia prior to edition 2018 we had a crate called "fuchsia_async" that we would commonly import as "extern crate fuchsia_async as async;", and could then use from other files in the same crate as "async::...". cargo fix fails on these examples. I'd expect it to do something like async::T -> r#async::T -> crate::r#async::T, but it just outputs a warning instead.

Note: this is with #![feature(raw_identifiers, crate_in_paths)].

[Mark-Simulacrum]

I believe we currently revert changes we've made if the crate still had warnings on the second compile, though I might be remembering wrong.

[alexcrichton]

Thanks for the report! This certainly isn't the only example of what we have to deal with here, there's also things like ::local_path::<::LocalType>(). A solution in cargo fix for this is being tracked at #5813, so I'm gonna close this in favor of that.