Doing std::move twice with the same unique_ptr

Question

What would happen if I called std::move twice with the same unique_ptr ?

unique_ptr<int> foo(new int(5));
unique_ptr<int> bar = move(foo);
unique_ptr<int> baz = move(foo);

PS: No, std::unique_ptr usage is NOT the same question. Both questions are about unique_ptr, and this is the only common thing between them.

Answer 1

Moving from a unique_ptr leaves it as null. So baz will end up being null too.