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// run-pass
// compile-flags: -C debug-assertions
#![feature(strict_provenance, pointer_is_aligned)]
#[repr(packed)]
struct Misaligner {
_head: u8,
tail: u64,
}
fn main() {
let memory = [Misaligner { _head: 0, tail: 0}, Misaligner { _head: 0, tail: 0}];
// Test that we can use addr_of! to get the address of a packed member which according to its
// type is not aligned, but because it is a projection from a packed type is a valid place.
let ptr0 = std::ptr::addr_of!(memory[0].tail);
let ptr1 = std::ptr::addr_of!(memory[0].tail);
// Even if ptr0 happens to be aligned by chance, ptr1 is not.
assert!(!ptr0.is_aligned() || !ptr1.is_aligned());
// And also test that we can get the addr of a packed struct then do a member read from it.
unsafe {
let ptr = std::ptr::addr_of!(memory[0]);
let _tail = (*ptr).tail;
let ptr = std::ptr::addr_of!(memory[1]);
let _tail = (*ptr).tail;
}
}
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