mirror of https://github.com/rust-lang/rust
36 lines
683 B
Rust
36 lines
683 B
Rust
// Test that we detect nested calls that could free pointers evaluated
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// for earlier arguments.
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fn rewrite(v: &mut Box<usize>) -> usize {
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*v = Box::new(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::new(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::new(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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