35 lines
1.1 KiB
Rust
35 lines
1.1 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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#![feature(test)]
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extern crate test;
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enum Void {}
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fn main() {
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let mut x: (Void, usize);
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let mut y = 42;
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x.1 = 13;
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// Make sure `y` stays on the stack.
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test::black_box(&mut y);
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// Check that the write to `x.1` did not overwrite `y`.
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// Note that this doesn't fail with optimizations enabled,
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// because we can't keep `x.1` on the stack, like we can `y`,
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// as we can't borrow partially initialized variables.
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assert_eq!(y.to_string(), "42");
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// Check that `(Void, usize)` has space for the `usize` field.
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assert_eq!(std::mem::size_of::<(Void, usize)>(),
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std::mem::size_of::<usize>());
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}
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