Given an expression e of type T, sizeof(e) returns the size in bytes of T. The
sizeof operator results in a value of type size_t. Also, sizeof(e) has no side effects because e
is not evaluated. Therefore, sizeof(sizeof(e)) is equivalent to sizeof(size_t).
In other words, sizeof(sizeof(e)) always gives the same result and does not depend on e, which is unlikely what was
expected.