8c4c698efb
Tighten spans for bad fields in struct deriving `Copy` r? `@estebank` Closes #89137 for good, I think Not sure if this is what you were looking for in https://github.com/rust-lang/rust/issues/89137#issuecomment-1146201791
For high-level intro to how type checking works in rustc, see the type checking chapter of the rustc dev guide.