+note: `Result<u32, &R>` defined here
+ --> $SRC_DIR/core/src/result.rs:LL:COL
+ |
+LL | / pub enum Result<T, E> {
+LL | | /// Contains the success value
+LL | | #[lang = "Ok"]
+LL | | #[stable(feature = "rust1", since = "1.0.0")]
+... |
+LL | | Err(#[stable(feature = "rust1", since = "1.0.0")] E),
+ | | ^^^ not covered
+LL | | }
+ | |_-