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//@ run-pass
#![allow(dead_code)]
use std::mem;
// Raising alignment
#[repr(align(16))]
enum Align16 {
Foo { foo: u32 },
Bar { bar: u32 },
}
// Raise alignment by maximum
#[repr(align(1), align(16))]
#[repr(align(32))]
#[repr(align(4))]
enum Align32 {
Foo,
Bar,
}
// Not reducing alignment
#[repr(align(4))]
enum AlsoAlign16 {
Foo { limb_with_align16: Align16 },
Bar,
}
// No niche for discriminant when used as limb
#[repr(align(16))]
struct NoNiche16(u64, u64);
// Discriminant will require extra space, but enum needs to stay compatible
// with alignment 16
#[repr(align(1))]
enum AnotherAlign16 {
Foo { limb_with_noniche16: NoNiche16 },
Bar,
Baz,
}
fn main() {
assert_eq!(mem::align_of::<Align16>(), 16);
assert_eq!(mem::size_of::<Align16>(), 16);
assert_eq!(mem::align_of::<Align32>(), 32);
assert_eq!(mem::size_of::<Align32>(), 32);
assert_eq!(mem::align_of::<AlsoAlign16>(), 16);
assert_eq!(mem::size_of::<AlsoAlign16>(), 16);
assert_eq!(mem::align_of::<AnotherAlign16>(), 16);
assert_eq!(mem::size_of::<AnotherAlign16>(), 32);
}
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