2021-11-13 14:40:26 -06:00
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// compile-flags: -Zmiri-tag-raw-pointers
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2020-12-29 12:27:23 -06:00
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// Taken from <https://github.com/rust-lang/unsafe-code-guidelines/issues/194#issuecomment-520934222>.
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use std::cell::Cell;
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fn helper(val: Box<Cell<u8>>, ptr: *const Cell<u8>) -> u8 {
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val.set(10);
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unsafe { (*ptr).set(20); } //~ ERROR does not have an appropriate item in the borrow stack
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val.get()
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}
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fn main() {
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let val: Box<Cell<u8>> = Box::new(Cell::new(25));
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let ptr: *const Cell<u8> = &*val;
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let res = helper(val, ptr);
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assert_eq!(res, 20);
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}
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