tests/ui/consts/const-extern-fn/const-extern-fn.rs

//@ run-pass

const extern "C" fn foo1(val: u8) -> u8 {
    val + 1
}

const extern "C" fn foo2(val: u8) -> u8 {
    val + 1
}

const unsafe extern "C" fn bar1(val: bool) -> bool {
    !val
}

const unsafe extern "C" fn bar2(val: bool) -> bool {
    !val
}

#[allow(improper_ctypes_definitions)]
const extern "C" fn unsize(x: &[u8; 3]) -> &[u8] {
    x
}

#[allow(improper_ctypes_definitions)]
const unsafe extern "C" fn closure() -> fn() {
    || {}
}

const unsafe extern "C" fn use_float() -> f32 {
    1.0 + 1.0
}

fn main() {
    let a: [u8; foo1(25) as usize] = [0; 26];
    let b: [u8; foo2(25) as usize] = [0; 26];
    assert_eq!(a, b);

    let bar1_res = unsafe { bar1(false) };
    let bar2_res = unsafe { bar2(false) };
    assert!(bar1_res);
    assert_eq!(bar1_res, bar2_res);

    let _foo1_cast: extern "C" fn(u8) -> u8 = foo1;
    let _foo2_cast: extern "C" fn(u8) -> u8 = foo2;
    let _bar1_cast: unsafe extern "C" fn(bool) -> bool = bar1;
    let _bar2_cast: unsafe extern "C" fn(bool) -> bool = bar2;

    unsize(&[0, 1, 2]);
    unsafe {
        closure();
    }
    unsafe {
        use_float();
    }
}