error[E0384]: cannot assign twice to immutable variable `a`
  --> $DIR/tainted-promoteds.rs:7:5
   |
LL |     let a = 0;
   |         - first assignment to `a`
LL |     a = &0 * &1 * &2 * &3;
   |     ^^^^^^^^^^^^^^^^^^^^^ cannot assign twice to immutable variable
   |
help: consider making this binding mutable
   |
LL |     let mut a = 0;
   |         +++

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0384`.