46 lines
1.1 KiB
Rust
46 lines
1.1 KiB
Rust
// Copyright 2012 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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// Test that we detect nested calls that could free pointers evaluated
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// for earlier arguments.
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#![feature(box_syntax)]
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fn rewrite(v: &mut Box<usize>) -> usize {
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*v = box 22;
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**v
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}
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fn add(v: &usize, w: usize) -> usize {
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*v + w
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}
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fn implicit() {
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let mut a: Box<_> = box 1;
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// Note the danger here:
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//
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// the pointer for the first argument has already been
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// evaluated, but it gets freed when evaluating the second
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// argument!
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add(
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&*a,
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rewrite(&mut a)); //~ ERROR cannot borrow
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}
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fn explicit() {
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let mut a: Box<_> = box 1;
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add(
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&*a,
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rewrite(&mut a)); //~ ERROR cannot borrow
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}
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fn main() {}
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