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