#link("c")
extern {
    fn puts(s: *const u8) -> i32;
    fn exit(code: i32) -> unreachable;
}

export fn _start() -> unreachable {
    let a : i32 = 1;
    let b = 2;
    let c : i32;
    // let d; // compile error
    puts("Hello, world!");
    exit(a + b);
}