error[E0004]: non-exhaustive patterns: `128_u8..=u8::MAX` not covered --> $DIR/guards.rs:12:11 | LL | match 0u8 { | ^^^ pattern `128_u8..=u8::MAX` not covered | = note: the matched value is of type `u8` help: ensure that all possible cases are being handled by adding a match arm with a wildcard pattern or an explicit pattern as shown | LL ~ 128 ..= 255 if true => {} LL + 128_u8..=u8::MAX => todo!() | error: aborting due to previous error For more information about this error, try `rustc --explain E0004`.