Hi all,
as part of my Rust Foundation Project Grant I'm currently working on improving error messages emitted by rustc for type mismatched based on the usage of trait heavy crates. The general idea here is to provide tools for crate authors to influence at least some error messages by themself. There are quite a lot of places where crate authors can provide much more context than a general rustc heuristic, just based on their knowledge onto how their crate is structured. My project goal is to collect different examples of such errors occurring in practice, classifying them based on what would be required to improve these messages and try various existing ideas on how such a integration in rustc's error reporting system could work in practice. With this post I'm looking forward to learn about cases of bad error messages you encountered in the past. I've created a repository to collect examples here. Please open an issue or even a PR with an example there or report them here inline.