Ralf Jung questions

Ralf Jung answers

• Does reading or writing a whole 32-bit word, even though we only have a reference to a part of it, result in undefined behaviour?
• Is transmuting PhantomData markers safe?
• Does std::ptr::write transfer the "uninitialized-ness" of the bytes it writes?
• Is it safe and defined behavior to transmute between a T and an UnsafeCell<T>?
• Is mem::forget(mem::uninitialized()) defined behavior?