34 lines
747 B
Rust
34 lines
747 B
Rust
// This test is a simple example of code that violates the dropck
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// rules: it pushes `&x` and `&y` into a bag (with dtor), but the
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// referenced data will be dropped before the bag is.
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fn main() {
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let mut v = Bag::new();
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let x: i8 = 3;
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let y: i8 = 4;
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v.push(&x);
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//~^ ERROR `x` does not live long enough
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v.push(&y);
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//~^ ERROR `y` does not live long enough
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assert_eq!(v.0, [&3, &4]);
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}
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//`Vec<T>` is #[may_dangle] w.r.t. `T`; putting a bag over its head
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// forces borrowck to treat dropping the bag as a potential use.
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struct Bag<T>(Vec<T>);
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impl<T> Drop for Bag<T> { fn drop(&mut self) { } }
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impl<T> Bag<T> {
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fn new() -> Self { Bag(Vec::new()) }
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fn push(&mut self, t: T) { self.0.push(t); }
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}
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