error: casting `i32` to `i64` may become silently lossy if you later change the type
  --> $DIR/types.rs:12:22
   |
LL |     let c_i64: i64 = c as i64;
   |                      ^^^^^^^^ help: try: `i64::from(c)`
   |
   = note: `-D clippy::cast-lossless` implied by `-D warnings`
   = help: to override `-D warnings` add `#[allow(clippy::cast_lossless)]`

error: aborting due to 1 previous error