rust/src/test/ui/unsafe/union_destructure.rs

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// run-pass
// revisions: mir thir
// [thir]compile-flags: -Z thir-unsafeck
#[derive(Copy, Clone)]
#[allow(dead_code)]
struct Pie {
slices: u8,
size: u8,
}
union Foo {
#[allow(dead_code)]
bar: i8,
baz: Pie
}
fn main() {
let u = Foo { bar: 5 };
let (Some(Foo { bar: _ }) | None) = Some(u);
let u = Foo { bar: 6 };
let (Some(Foo { bar: _ }) | Some(Foo { bar: _ }) | None) = Some(u);
unsafe {
let u = Foo { bar: 7 };
let (Foo { bar } | Foo { bar }) = u;
assert_eq!(bar, 7)
}
let u = Foo { bar: 8 };
match Some(u) {
Some(Foo { bar: _ }) => 3,
None => 4,
};
let u = Foo { bar: 9 };
unsafe { //[mir]~ WARNING unnecessary `unsafe` block
match u {
Foo { baz: Pie { .. } } => {},
};
}
let u = Foo { bar: 10 };
unsafe { //[mir]~ WARNING unnecessary `unsafe` block
match u {
Foo { baz: Pie { slices: _, size: _ } } => {},
};
}
let u = Foo { bar: 11 };
match u {
Foo { baz: _ } => {},
};
}