mirror of https://github.com/rust-lang/rust
42 lines
635 B
Rust
42 lines
635 B
Rust
//@ run-pass
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#![allow(dead_code)]
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use std::mem::needs_drop;
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use std::mem::ManuallyDrop;
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struct NeedDrop;
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impl Drop for NeedDrop {
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fn drop(&mut self) {}
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}
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union UnionOk1<T> {
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empty: (),
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value: ManuallyDrop<T>,
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}
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union UnionOk2 {
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value: ManuallyDrop<NeedDrop>,
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}
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#[allow(dead_code)]
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union UnionOk3<T: Copy> {
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empty: (),
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value: T,
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}
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trait Foo {}
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trait ImpliesCopy: Copy {}
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#[allow(dead_code)]
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union UnionOk4<T: ImpliesCopy> {
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value: T,
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}
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fn main() {
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// NeedDrop should not make needs_drop true
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assert!(!needs_drop::<UnionOk1<NeedDrop>>());
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assert!(!needs_drop::<UnionOk3<&dyn Foo>>());
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}
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