#![allow(unused_variables)]
fn main() {
    let size = 4;
    let mut x: Vec<i32> = Vec::with_capacity(size);
    let x_ptr = x.as_mut_ptr();
    unsafe {
        for i in 0..size {
            *x_ptr.add(i) = i as i32;
        }
        x.set_len(size);
    }
    assert_eq!(&* x, & [0, 1, 2, 3]);
}