mirror of https://github.com/rust-lang/rust
33 lines
657 B
Rust
33 lines
657 B
Rust
use std::mem::ManuallyDrop;
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// Non-copy
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struct A;
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struct B;
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union U {
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a: ManuallyDrop<A>,
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b: ManuallyDrop<B>,
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}
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fn main() {
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unsafe {
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{
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let mut u = U { a: ManuallyDrop::new(A) };
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let a = u.a;
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let a = u.a; //~ ERROR use of moved value: `u`
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}
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{
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let mut u = U { a: ManuallyDrop::new(A) };
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let a = u.a;
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u.a = ManuallyDrop::new(A);
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let a = u.a; // OK
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}
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{
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let mut u = U { a: ManuallyDrop::new(A) };
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let a = u.a;
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u.b = ManuallyDrop::new(B);
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let a = u.a; // OK
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}
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}
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}
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