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			35 lines
		
	
	
		
			709 B
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			35 lines
		
	
	
		
			709 B
		
	
	
	
		
			Rust
		
	
	
	
	
	
| #![allow(dead_code, cenum_impl_drop_cast)]
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| 
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| // check dtor calling order when casting enums.
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| 
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| use std::sync::atomic;
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| use std::sync::atomic::Ordering;
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| use std::mem;
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| 
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| enum E {
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|     A = 0,
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|     B = 1,
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|     C = 2
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| }
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| 
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| static FLAG: atomic::AtomicUsize = atomic::AtomicUsize::new(0);
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| 
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| impl Drop for E {
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|     fn drop(&mut self) {
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|         // avoid dtor loop
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|         unsafe { mem::forget(mem::replace(self, E::B)) };
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| 
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|         FLAG.store(FLAG.load(Ordering::SeqCst)+1, Ordering::SeqCst);
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|     }
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| }
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| 
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| fn main() {
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|     assert_eq!(FLAG.load(Ordering::SeqCst), 0);
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|     {
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|         let e = E::C;
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|         assert_eq!(e as u32, 2);
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|         assert_eq!(FLAG.load(Ordering::SeqCst), 1);
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|     }
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|     assert_eq!(FLAG.load(Ordering::SeqCst), 1);
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| }
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