error[E0054]: cannot cast as `bool`
  --> $DIR/E0054.rs:13:24
   |
LL |     let x_is_nonzero = x as bool; //~ ERROR E0054
   |                        ^^^^^^^^^ unsupported cast
   |
   = help: compare with zero instead

error: aborting due to previous error

If you want more information on this error, try using "rustc --explain E0054"