fib/
fib.rs

1#[unsafe(no_mangle)]
2pub extern "C" fn fib(n: u32) -> u32 {
3    let mut a = 1;
4    let mut b = 1;
5    for _ in 0..n {
6        let t = a;
7        a = b;
8        b += t;
9    }
10    return b;
11}