message: Only enable `i128_type` when necessary.
diff: // This library relies on the Rust nightly compiler's `i128_type` feature.
  -#![feature(i128_type)]
  +// If that's not okay for you, disable the u128-support feature. (Pass
  +// --no-default-features for example.)
  +#![cfg_attr(feature = "u128-support", feature(i128_type))]
  // `clippy` is a code linting tool for improving code quality by catching
  // common mistakes or strange code patterns. If the `clippy` feature is
  