23 lines
775 B
Rust
23 lines
775 B
Rust
fn main() {
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// The slack between allocations is random.
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// Loop a few times to hit the zero-slack case.
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for _ in 0..1024 {
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let n = 0u64;
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let ptr: *const u64 = &n;
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// Allocate a new stack variable whose lifetime quickly ends.
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// If there's a chance that &m == ptr.add(1), then an int-to-ptr cast of
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// that value will have ambiguous provenance between n and m.
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// See https://github.com/rust-lang/miri/issues/1866#issuecomment-985770125
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{
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let m = 0u64;
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let _ = &m as *const u64;
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}
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let iptr = ptr as usize;
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let zst = (iptr + 8) as *const ();
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// This is a ZST ptr just at the end of `n`, so it should be valid to deref.
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unsafe { *zst }
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}
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}
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