error[E0384]: cannot assign twice to immutable variable `a` --> $DIR/tainted-promoteds.rs:7:5 | LL | let a = 0; | - | | | first assignment to `a` | help: consider making this binding mutable: `mut a` LL | a = &0 * &1 * &2 * &3; | ^^^^^^^^^^^^^^^^^^^^^ cannot assign twice to immutable variable error: aborting due to 1 previous error For more information about this error, try `rustc --explain E0384`.