>[оверквотинг удален]
> fn main() {
>     let mut x: i32 = 0;
>     for i in 0..1000_000_000 {
>         unsafe {
>            
> x = print_num(i);
>         }
>     }
>     println!("{}", x);
> }

go build main.go
main.go:2:1: expected 'package', found 'func'