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// run-pass
// revisions: mirunsafeck thirunsafeck
// [thirunsafeck]compile-flags: -Z thir-unsafeck
#[repr(C)]
#[derive(Copy, Clone)]
struct Pair<T, U>(T, U);
#[repr(C)]
#[derive(Copy, Clone)]
struct Triple<T>(T, T, T);
#[repr(C)]
union U<A, B>
where
A: Copy, B: Copy
{
a: Pair<A, A>,
b: B,
}
#[repr(C)]
union W<A, B>
where
A: Copy, B: Copy
{
a: A,
b: B,
}
#[cfg(target_endian = "little")]
unsafe fn check() {
let mut u = U::<u8, u16> { b: 0xDE_DE };
u.a.0 = 0xBE;
assert_eq!(u.b, 0xDE_BE);
let mut u = U::<u16, u32> { b: 0xDEAD_DEAD };
u.a.0 = 0xBEEF;
assert_eq!(u.b, 0xDEAD_BEEF);
let mut u = U::<u32, u64> { b: 0xDEADBEEF_DEADBEEF };
u.a.0 = 0xBAADF00D;
assert_eq!(u.b, 0xDEADBEEF_BAADF00D);
let mut w = W::<Pair<Triple<u8>, u8>, u32> { b: 0xDEAD_DEAD };
w.a.0 = Triple(0, 0, 0);
assert_eq!(w.b, 0xDE00_0000);
let mut w = W::<Pair<u8, Triple<u8>>, u32> { b: 0xDEAD_DEAD };
w.a.1 = Triple(0, 0, 0);
assert_eq!(w.b, 0x0000_00AD);
}
#[cfg(target_endian = "big")]
unsafe fn check() {
let mut u = U::<u8, u16> { b: 0xDE_DE };
u.a.0 = 0xBE;
assert_eq!(u.b, 0xBE_DE);
let mut u = U::<u16, u32> { b: 0xDEAD_DEAD };
u.a.0 = 0xBEEF;
assert_eq!(u.b, 0xBEEF_DEAD);
let mut u = U::<u32, u64> { b: 0xDEADBEEF_DEADBEEF };
u.a.0 = 0xBAADF00D;
assert_eq!(u.b, 0xBAADF00D_DEADBEEF);
let mut w = W::<Pair<Triple<u8>, u8>, u32> { b: 0xDEAD_DEAD };
w.a.0 = Triple(0, 0, 0);
assert_eq!(w.b, 0x0000_00AD);
let mut w = W::<Pair<u8, Triple<u8>>, u32> { b: 0xDEAD_DEAD };
w.a.1 = Triple(0, 0, 0);
assert_eq!(w.b, 0xDE00_0000);
}
fn main() {
unsafe {
check();
}
}
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