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31 lines
786 B
Rust
31 lines
786 B
Rust
// Basic test for liveness constraints: the region (`R1`) that appears
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// in the type of `p` must include everything until `p` is dropped
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// because of destructor. (Note that the stderr also identifies this
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// destructor in the error message.)
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#![allow(warnings)]
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#![feature(dropck_eyepatch)]
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fn use_x(_: usize) -> bool { true }
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fn main() {
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let mut v = [1, 2, 3];
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let p: WrapMayNotDangle<&usize> = WrapMayNotDangle { value: &v[0] };
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if true {
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use_x(*p.value);
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} else {
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use_x(22);
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v[0] += 1; //~ ERROR cannot assign to `v[_]` because it is borrowed
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}
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v[0] += 1; //~ ERROR cannot assign to `v[_]` because it is borrowed
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}
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struct WrapMayNotDangle<T> {
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value: T
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}
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impl<T> Drop for WrapMayNotDangle<T> {
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fn drop(&mut self) { }
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}
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