mirror of https://github.com/rust-lang/rust.git
61 lines
1014 B
Rust
61 lines
1014 B
Rust
// run-pass
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// revisions: mirunsafeck thirunsafeck
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// [thirunsafeck]compile-flags: -Z thir-unsafeck
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#![allow(dead_code)]
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#![allow(unused_variables)]
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// Drop works for union itself.
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#[derive(Copy, Clone)]
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struct S;
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union U {
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a: u8
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}
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union W {
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a: S,
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}
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union Y {
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a: S,
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}
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impl Drop for U {
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fn drop(&mut self) {
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unsafe { CHECK += 1; }
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}
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}
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impl Drop for W {
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fn drop(&mut self) {
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unsafe { CHECK += 1; }
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}
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}
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static mut CHECK: u8 = 0;
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fn main() {
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unsafe {
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assert_eq!(CHECK, 0);
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{
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let u = U { a: 1 };
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}
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assert_eq!(CHECK, 1); // 1, dtor of U is called
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{
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let w = W { a: S };
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}
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assert_eq!(CHECK, 2); // 2, dtor of W is called
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{
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let y = Y { a: S };
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}
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assert_eq!(CHECK, 2); // 2, Y has no dtor
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{
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let u2 = U { a: 1 };
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std::mem::forget(u2);
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}
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assert_eq!(CHECK, 2); // 2, dtor of U *not* called for u2
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}
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}
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