------------------------
+The `i128_type` feature adds support for 128 bit signed and unsigned integer
+types.
+```rust
+#![feature(i128_type)]
+
+fn main() {
+ assert_eq!(1u128 + 1u128, 2u128);
+ assert_eq!(u128::min_value(), 0);
+ assert_eq!(u128::max_value(), 340282366920938463463374607431768211455);
+
+ assert_eq!(1i128 - 2i128, -1i128);
+ assert_eq!(i128::min_value(), -170141183460469231731687303715884105728);
+ assert_eq!(i128::max_value(), 170141183460469231731687303715884105727);
+}
+```