64 lines
1.2 KiB
Rust
64 lines
1.2 KiB
Rust
// run-pass
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#![allow(dead_code)]
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use std::mem::{size_of, size_of_val, align_of, align_of_val};
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#[repr(align(16))]
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pub union U16 {
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a: u8,
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b: u32
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}
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fn main() {
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assert_eq!(align_of::<U16>(), 16);
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assert_eq!(size_of::<U16>(), 16);
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let u = U16 { a: 10 };
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unsafe {
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assert_eq!(align_of_val(&u.a), 1);
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assert_eq!(size_of_val(&u.a), 1);
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assert_eq!(u.a, 10);
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}
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let u = U16 { b: 11 };
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unsafe {
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assert_eq!(align_of_val(&u.b), 4);
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assert_eq!(size_of_val(&u.b), 4);
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assert_eq!(u.b, 11);
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}
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hybrid::check_hybrid();
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}
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mod hybrid {
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use std::mem::{size_of, align_of};
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#[repr(align(16))]
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#[derive(Copy, Clone)]
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struct S1 {
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a: u16,
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b: u8,
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}
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#[repr(align(32))]
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union U {
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s: S1,
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c: u16,
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}
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#[repr(align(64))]
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struct S2 {
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d: u8,
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u: U,
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}
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pub fn check_hybrid() {
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assert_eq!(align_of::<S1>(), 16);
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assert_eq!(size_of::<S1>(), 16);
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assert_eq!(align_of::<U>(), 32);
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assert_eq!(size_of::<U>(), 32);
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assert_eq!(align_of::<S2>(), 64);
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assert_eq!(size_of::<S2>(), 64);
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}
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}
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