error[E0594]: cannot assign to `x`, as it is not declared as mutable --> $DIR/issue-46023.rs:5:9 | LL | let x = 0; | - help: consider changing this to be mutable: `mut x` ... LL | x = 1; | ^^^^^ cannot assign error: aborting due to previous error For more information about this error, try `rustc --explain E0594`.