#[repr(align(16))]
struct Foo {
    a: u8,
    b: u8
}



fn main() {
    use std::mem;

    let foo = Foo { a: 127, b: 63 };

    let foo_ptr : *const Foo = &foo;
    let a_ptr : *const u8 = &foo.a;
    let b_ptr : *const u8 = &foo.b;

    let offset_a = (a_ptr as usize) - (foo_ptr as usize);
    let offset_b = (b_ptr as usize) - (foo_ptr as usize);

    println!("a={}, b={}", offset_a, offset_b);
}