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			34 lines
		
	
	
		
			677 B
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			34 lines
		
	
	
		
			677 B
		
	
	
	
		
			Rust
		
	
	
	
	
	
| // compile-flags: -O
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| #![feature(c_unwind)]
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| #![crate_type = "lib"]
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| 
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| pub struct Foo([u8; 1000]);
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| 
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| extern "C" {
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|     fn init(p: *mut Foo);
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| }
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| 
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| pub fn new_from_uninit() -> Foo {
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|     // CHECK-LABEL: new_from_uninit
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|     // CHECK-NOT: call void @llvm.memcpy.
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|     let mut x = std::mem::MaybeUninit::uninit();
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|     unsafe {
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|         init(x.as_mut_ptr());
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|         x.assume_init()
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|     }
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| }
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| 
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| extern "C-unwind" {
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|     fn init_unwind(p: *mut Foo);
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| }
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| 
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| pub fn new_from_uninit_unwind() -> Foo {
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|     // CHECK-LABEL: new_from_uninit
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|     // CHECK: call void @llvm.memcpy.
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|     let mut x = std::mem::MaybeUninit::uninit();
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|     unsafe {
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|         init_unwind(x.as_mut_ptr());
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|         x.assume_init()
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|     }
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| }
 | 
