I’m trying to verify my understanding of Rust’s aliasing rules regarding UnsafeCell<T>.

It seems that if you have multiple &UnsafeCell<T> references and use one to create a temporary &mut T for writing, you inevitably have both types of pointers pointing to the same memory at the same time.

My reasoning is that since UnsafeCell<T> explicitly opts out of the standard &T immutability/noalias guarantees, this "coexistence" might actually be legal within the memory model. Is it correct to say that as long as UnsafeCell is involved, the strict exclusivity of &mut T is relaxed to allow these overlaps?

I’d appreciate any insights on whether this interpretation is correct.

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