mirror of https://github.com/rust-lang/rust
93 lines
2.2 KiB
Rust
93 lines
2.2 KiB
Rust
//@ run-pass
|
|
use std::fmt;
|
|
|
|
#[repr(C)]
|
|
enum CEnum {
|
|
Hello = 30,
|
|
World = 60
|
|
}
|
|
|
|
fn test1(c: CEnum) -> i32 {
|
|
let c2 = CEnum::Hello;
|
|
match (c, c2) {
|
|
(CEnum::Hello, CEnum::Hello) => 42,
|
|
(CEnum::World, CEnum::Hello) => 0,
|
|
_ => 1
|
|
}
|
|
}
|
|
|
|
#[repr(packed)]
|
|
struct Pakd {
|
|
a: u64,
|
|
b: u32,
|
|
c: u16,
|
|
d: u8,
|
|
e: ()
|
|
}
|
|
|
|
// It is unsafe to use #[derive(Debug)] on a packed struct because the code generated by the derive
|
|
// macro takes references to the fields instead of accessing them directly.
|
|
impl fmt::Debug for Pakd {
|
|
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
|
|
// It's important that we load the fields into locals by-value here. This will do safe
|
|
// unaligned loads into the locals, then pass references to the properly-aligned locals to
|
|
// the formatting code.
|
|
let Pakd { a, b, c, d, e } = *self;
|
|
f.debug_struct("Pakd")
|
|
.field("a", &a)
|
|
.field("b", &b)
|
|
.field("c", &c)
|
|
.field("d", &d)
|
|
.field("e", &e)
|
|
.finish()
|
|
}
|
|
}
|
|
|
|
// It is unsafe to use #[derive(PartialEq)] on a packed struct because the code generated by the
|
|
// derive macro takes references to the fields instead of accessing them directly.
|
|
impl PartialEq for Pakd {
|
|
fn eq(&self, other: &Pakd) -> bool {
|
|
self.a == other.a &&
|
|
self.b == other.b &&
|
|
self.c == other.c &&
|
|
self.d == other.d &&
|
|
self.e == other.e
|
|
}
|
|
}
|
|
|
|
impl Drop for Pakd {
|
|
fn drop(&mut self) {}
|
|
}
|
|
|
|
fn test2() -> Pakd {
|
|
Pakd { a: 42, b: 42, c: 42, d: 42, e: () }
|
|
}
|
|
|
|
#[derive(PartialEq, Debug)]
|
|
struct TupleLike(u64, u32);
|
|
|
|
fn test3() -> TupleLike {
|
|
TupleLike(42, 42)
|
|
}
|
|
|
|
fn test4(x: fn(u64, u32) -> TupleLike) -> (TupleLike, TupleLike) {
|
|
let y = TupleLike;
|
|
(x(42, 84), y(42, 84))
|
|
}
|
|
|
|
fn test5(x: fn(u32) -> Option<u32>) -> (Option<u32>, Option<u32>) {
|
|
let y = Some;
|
|
(x(42), y(42))
|
|
}
|
|
|
|
fn main() {
|
|
assert_eq!(test1(CEnum::Hello), 42);
|
|
assert_eq!(test1(CEnum::World), 0);
|
|
assert_eq!(test2(), Pakd { a: 42, b: 42, c: 42, d: 42, e: () });
|
|
assert_eq!(test3(), TupleLike(42, 42));
|
|
let t4 = test4(TupleLike);
|
|
assert_eq!(t4.0, t4.1);
|
|
let t5 = test5(Some);
|
|
assert_eq!(t5.0, t5.1);
|
|
}
|