2 let (x, y) = (1u32, 2u32);
4 let add = std::intrinsics::unchecked_add(x, y); //~ ERROR use of unstable library feature
5 let sub = std::intrinsics::unchecked_sub(x, y); //~ ERROR use of unstable library feature
6 let mul = std::intrinsics::unchecked_mul(x, y); //~ ERROR use of unstable library feature