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//@ run-pass
#![allow(dead_code)]
#![allow(non_snake_case)]
use std::mem::{size_of, size_of_val, align_of, align_of_val};
struct S {
a: u16,
b: [u8; 3],
}
#[repr(packed)]
struct Sp1 {
a: u16,
b: [u8; 3],
}
#[repr(packed(2))]
struct Sp2 {
a: u16,
b: [u8; 3],
}
union U {
a: u16,
b: [u8; 3],
}
#[repr(packed)]
union Up1 {
a: u16,
b: [u8; 3],
}
#[repr(packed(2))]
union Up2 {
a: u16,
b: [u8; 3],
}
#[repr(C, packed(4))]
union Up4c {
a: u16,
b: [u8; 3],
}
const CS: S = S { a: 0, b: [0, 0, 0] };
const CSP1: Sp1 = Sp1 { a: 0, b: [0, 0, 0] };
const CSP2: Sp2 = Sp2 { a: 0, b: [0, 0, 0] };
const CU: U = U { b: [0, 0, 0] };
const CUP1: Up1 = Up1 { b: [0, 0, 0] };
const CUP2: Up2 = Up2 { b: [0, 0, 0] };
const CUP4C: Up4c = Up4c { b: [0, 0, 0] };
fn main() {
let s = S { a: 0, b: [0, 0, 0] };
assert_eq!(size_of::<S>(), 6);
assert_eq!(size_of_val(&s), 6);
assert_eq!(size_of_val(&CS), 6);
assert_eq!(align_of::<S>(), 2);
assert_eq!(align_of_val(&s), 2);
assert_eq!(align_of_val(&CS), 2);
let sp1 = Sp1 { a: 0, b: [0, 0, 0] };
assert_eq!(size_of::<Sp1>(), 5);
assert_eq!(size_of_val(&sp1), 5);
assert_eq!(size_of_val(&CSP1), 5);
assert_eq!(align_of::<Sp1>(), 1);
assert_eq!(align_of_val(&sp1), 1);
assert_eq!(align_of_val(&CSP1), 1);
let sp2 = Sp2 { a: 0, b: [0, 0, 0] };
assert_eq!(size_of::<Sp2>(), 6);
assert_eq!(size_of_val(&sp2), 6);
assert_eq!(size_of_val(&CSP2), 6);
assert_eq!(align_of::<Sp2>(), 2);
assert_eq!(align_of_val(&sp2), 2);
assert_eq!(align_of_val(&CSP2), 2);
let u = U { b: [0, 0, 0] };
assert_eq!(size_of::<U>(), 4);
assert_eq!(size_of_val(&u), 4);
assert_eq!(size_of_val(&CU), 4);
assert_eq!(align_of::<U>(), 2);
assert_eq!(align_of_val(&u), 2);
assert_eq!(align_of_val(&CU), 2);
let Up1 = Up1 { b: [0, 0, 0] };
assert_eq!(size_of::<Up1>(), 3);
assert_eq!(size_of_val(&Up1), 3);
assert_eq!(size_of_val(&CUP1), 3);
assert_eq!(align_of::<Up1>(), 1);
assert_eq!(align_of_val(&Up1), 1);
assert_eq!(align_of_val(&CUP1), 1);
let up2 = Up2 { b: [0, 0, 0] };
assert_eq!(size_of::<Up2>(), 4);
assert_eq!(size_of_val(&up2), 4);
assert_eq!(size_of_val(&CUP2), 4);
assert_eq!(align_of::<Up2>(), 2);
assert_eq!(align_of_val(&up2), 2);
assert_eq!(align_of_val(&CUP2), 2);
let up4c = Up4c { b: [0, 0, 0] };
assert_eq!(size_of::<Up4c>(), 4);
assert_eq!(size_of_val(&up4c), 4);
assert_eq!(size_of_val(&CUP4C), 4);
assert_eq!(align_of::<Up4c>(), 2);
assert_eq!(align_of_val(&up4c), 2);
assert_eq!(align_of_val(&CUP4C), 2);
hybrid::check_hybrid();
}
mod hybrid {
use std::mem::{size_of, align_of};
#[repr(packed)]
#[derive(Copy, Clone)]
struct S1 {
a: u16,
b: u8,
}
#[repr(packed)]
union U {
s: S1,
c: u16,
}
#[repr(packed)]
struct S2 {
d: u8,
u: U,
}
#[repr(C, packed(2))]
struct S1C {
a: u16,
b: u8,
}
#[repr(C, packed(2))]
union UC {
s: S1,
c: u16,
}
#[repr(C, packed(2))]
struct S2C {
d: u8,
u: UC,
}
pub fn check_hybrid() {
assert_eq!(align_of::<S1>(), 1);
assert_eq!(size_of::<S1>(), 3);
assert_eq!(align_of::<U>(), 1);
assert_eq!(size_of::<U>(), 3);
assert_eq!(align_of::<S2>(), 1);
assert_eq!(size_of::<S2>(), 4);
assert_eq!(align_of::<S1C>(), 2);
assert_eq!(size_of::<S1C>(), 4);
assert_eq!(align_of::<UC>(), 2);
assert_eq!(size_of::<UC>(), 4);
assert_eq!(align_of::<S2C>(), 2);
assert_eq!(size_of::<S2C>(), 6);
}
}
|
