2020-11-02 06:40:12 -06:00
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// ignore-windows: Concurrency on Windows is not supported yet.
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2020-11-01 19:46:42 -06:00
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use std::thread::spawn;
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use std::sync::atomic::{AtomicUsize, Ordering};
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#[derive(Copy, Clone)]
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struct EvilSend<T>(pub T);
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unsafe impl<T> Send for EvilSend<T> {}
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unsafe impl<T> Sync for EvilSend<T> {}
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static SYNC: AtomicUsize = AtomicUsize::new(0);
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pub fn main() {
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let mut a = 0u32;
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let b = &mut a as *mut u32;
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let c = EvilSend(b);
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unsafe {
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let j1 = spawn(move || {
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*c.0 = 1;
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SYNC.store(1, Ordering::Release);
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});
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let j2 = spawn(move || {
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if SYNC.load(Ordering::Acquire) == 1 {
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SYNC.store(2, Ordering::Relaxed);
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}
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});
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let j3 = spawn(move || {
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if SYNC.load(Ordering::Acquire) == 2 {
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*c.0 //~ ERROR Data race
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2020-11-22 11:28:12 -06:00
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} else {
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2020-11-01 19:46:42 -06:00
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0
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}
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});
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j1.join().unwrap();
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j2.join().unwrap();
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j3.join().unwrap();
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}
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2020-11-02 07:08:09 -06:00
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}
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