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EXP62-CPP-EX1: It is permissible to access the bits of an object representation when that access is otherwise unobservable in well-defined code. Specifically, reading bits that are not part of the value representation is permissible when there is no reliance or assumptions placed on their values, and writing bits that are not part of the value representation is only permissible when those bits are padding bits. This exception does not permit writing to bits that are part of the object representation aside from padding bits, such as overwriting a vtable pointer.
For instance, it is acceptable to call std::memcpy() on an object containing a bit-field, as in the following example, because the read and write of the padding bits cannot be observed. However, the code still must comply with OOP57-CPP. Prefer special member functions and overloaded operators to C Standard Library functions.
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