src/test/ui/nullable-pointer-size.rs

// run-pass

#![allow(dead_code)]

use std::mem;

enum E<T> { Thing(isize, T), Nothing((), ((), ()), [i8; 0]) }
struct S<T>(isize, T);

// These are macros so we get useful assert messages.

macro_rules! check_option {
    ($T:ty) => {
        assert_eq!(mem::size_of::<Option<$T>>(), mem::size_of::<$T>());
    }
}

macro_rules! check_fancy {
    ($T:ty) => {
        assert_eq!(mem::size_of::<E<$T>>(), mem::size_of::<S<$T>>());
    }
}

macro_rules! check_type {
    ($T:ty) => {{
        check_option!($T);
        check_fancy!($T);
    }}
}

pub fn main() {
    check_type!(&'static isize);
    check_type!(Box<isize>);
    check_type!(extern fn());
}