2018-10-29 13:48:43 -05:00
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// A callee may not read the destination of our `&mut` without
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// us noticing.
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2022-04-30 13:07:36 -05:00
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#[rustfmt::skip] // rustfmt bug: https://github.com/rust-lang/rustfmt/issues/5391
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2018-10-29 13:48:43 -05:00
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fn main() {
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let mut x = 15;
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let xraw = &mut x as *mut _;
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2019-02-15 19:43:56 -06:00
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let xref = unsafe { &mut *xraw }; // derived from raw, so using raw is still ok...
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2018-10-29 13:48:43 -05:00
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callee(xraw);
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let _val = *xref; // ...but any use of raw will invalidate our ref.
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2022-07-13 17:59:33 -05:00
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//~^ ERROR: /read access .* tag does not exist in the borrow stack/
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2018-10-29 13:48:43 -05:00
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}
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fn callee(xraw: *mut i32) {
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// We are a bit sneaky: We first create a shared ref, exploiting the reborrowing rules,
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// and then we read through that.
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let shr = unsafe { &*xraw };
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let _val = *shr;
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}
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