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//@ run-pass
#![allow(dead_code)]
#[repr(u32)]
enum Tag {
I,
F,
}
#[repr(C)]
union U {
i: i32,
f: f32,
}
#[repr(C)]
struct Value {
tag: Tag,
u: U,
}
fn is_zero(v: Value) -> bool {
unsafe {
match v {
Value { tag: Tag::I, u: U { i: 0 } } => true,
Value { tag: Tag::F, u: U { f: 0.0 } } => true,
_ => false,
}
}
}
union W {
a: u8,
b: u8,
}
fn refut(w: W) {
unsafe {
match w {
W { a: 10 } => {
panic!();
}
W { b } => {
assert_eq!(b, 11);
}
}
}
}
fn main() {
let v = Value { tag: Tag::I, u: U { i: 1 } };
assert_eq!(is_zero(v), false);
let w = W { a: 11 };
refut(w);
}
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