rust/tests/run-pass/transmute_fat.rs

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// Stacked Borrows disallows this becuase the reference is never cast to a raw pointer.
// compile-flags: -Zmiri-disable-stacked-borrows
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fn main() {
// If we are careful, we can exploit data layout...
let raw = unsafe {
std::mem::transmute::<&[u8], [usize; 2]>(&[42])
};
let ptr = raw[0] + raw[1];
let ptr = ptr as *const u8;
// The pointer is one-past-the end, but we decrement it into bounds before using it
assert_eq!(unsafe { *ptr.offset(-1) }, 42);
}