19 lines
568 B
Rust
19 lines
568 B
Rust
// A callee may not read the destination of our `&mut` without
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// us noticing.
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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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let xref = unsafe { &mut *xraw }; // derived from raw, so using raw is still ok...
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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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//~^ ERROR: borrow stack
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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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