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// 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);
}
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