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// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
union DummyUnion {
u8: u8,
bool: bool,
}
#[repr(C)]
#[derive(Copy, Clone)]
enum Enum {
A,
B,
C,
}
#[derive(Copy, Clone)]
union Foo {
a: bool,
b: Enum,
}
union Bar {
foo: Foo,
u8: u8,
}
// the value is not valid for bools
const BAD_BOOL: bool = unsafe { DummyUnion { u8: 42 }.bool};
//~^ ERROR this constant likely exhibits undefined behavior
// The value is not valid for any union variant, but that's fine
// unions are just a convenient way to transmute bits around
const BAD_UNION: Foo = unsafe { Bar { u8: 42 }.foo };
fn main() {
}
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