rust/tests/ui/repr/repr_c_int_align.rs

47 lines
854 B
Rust

//@ run-pass
//@ compile-flags: -O
#![allow(dead_code)]
#[repr(C, u8)]
enum ReprCu8 {
A(u16),
B,
}
#[repr(u8)]
enum Repru8 {
A(u16),
B,
}
#[repr(C)]
struct ReprC {
tag: u8,
padding: u8,
payload: u16,
}
fn main() {
// Test `repr(C, u8)`.
let r1 = ReprC { tag: 0, padding: 0, payload: 0 };
let r2 = ReprC { tag: 0, padding: 1, payload: 1 };
let t1: &ReprCu8 = unsafe { std::mem::transmute(&r1) };
let t2: &ReprCu8 = unsafe { std::mem::transmute(&r2) };
match (t1, t2) {
(ReprCu8::A(_), ReprCu8::A(_)) => (),
_ => assert!(false)
};
// Test `repr(u8)`.
let t1: &Repru8 = unsafe { std::mem::transmute(&r1) };
let t2: &Repru8 = unsafe { std::mem::transmute(&r2) };
match (t1, t2) {
(Repru8::A(_), Repru8::A(_)) => (),
_ => assert!(false)
};
}