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// run-pass
#![allow(dead_code)]
#![allow(deprecated)]
#![allow(non_snake_case)]
use std::mem;
enum Tag<A,B> {
VarA(A),
VarB(B),
}
struct Rec<A,B> {
chA: u8,
tA: Tag<A,B>,
chB: u8,
tB: Tag<A,B>,
}
fn mk_rec<A,B>(a: A, b: B) -> Rec<A,B> {
Rec { chA:0, tA:Tag::VarA(a), chB:1, tB:Tag::VarB(b) }
}
fn is_aligned<A>(amnt: usize, u: &A) -> bool {
let p: usize = unsafe { mem::transmute(u) };
return (p & (amnt-1)) == 0;
}
fn variant_data_is_aligned<A,B>(amnt: usize, u: &Tag<A,B>) -> bool {
match u {
&Tag::VarA(ref a) => is_aligned(amnt, a),
&Tag::VarB(ref b) => is_aligned(amnt, b)
}
}
pub fn main() {
let u64_align = std::mem::min_align_of::<u64>();
let x = mk_rec(22u64, 23u64);
assert!(is_aligned(u64_align, &x.tA));
assert!(variant_data_is_aligned(u64_align, &x.tA));
assert!(is_aligned(u64_align, &x.tB));
assert!(variant_data_is_aligned(u64_align, &x.tB));
let x = mk_rec(22u64, 23u32);
assert!(is_aligned(u64_align, &x.tA));
assert!(variant_data_is_aligned(u64_align, &x.tA));
assert!(is_aligned(u64_align, &x.tB));
assert!(variant_data_is_aligned(4, &x.tB));
let x = mk_rec(22u32, 23u64);
assert!(is_aligned(u64_align, &x.tA));
assert!(variant_data_is_aligned(4, &x.tA));
assert!(is_aligned(u64_align, &x.tB));
assert!(variant_data_is_aligned(u64_align, &x.tB));
let x = mk_rec(22u32, 23u32);
assert!(is_aligned(4, &x.tA));
assert!(variant_data_is_aligned(4, &x.tA));
assert!(is_aligned(4, &x.tB));
assert!(variant_data_is_aligned(4, &x.tB));
let x = mk_rec(22f64, 23f64);
assert!(is_aligned(u64_align, &x.tA));
assert!(variant_data_is_aligned(u64_align, &x.tA));
assert!(is_aligned(u64_align, &x.tB));
assert!(variant_data_is_aligned(u64_align, &x.tB));
}
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