8a3ad4942c
Output correct type responsible for structural match violation Previously we included the outermost type that caused a structural match violation in the error message and stated that that type must be annotated with `#[derive(Eq, PartialEq)]` even if it already had that annotation. This PR outputs the correct type in the error message. Fixes https://github.com/rust-lang/rust/issues/97278
For high-level intro to how type checking works in rustc, see the type checking chapter of the rustc dev guide.