C++0x will relax several rules with regard to the POD definition.
A class/struct is considered a POD if it is trivial, standard-layout, and it has no non-static members that are not PODs. A trivial class or struct is defined as one that:
1. Has a trivial default constructor. This may use the default constructor syntax (SomeConstructor() = default
2. Has a trivial copy constructor, which may use the default syntax.
3. Has a trivial copy assignment operator, which may use the default syntax.
4. Has a trivial destructor, which may not be virtual.
A standard-layout class or struct is defined as one that:
1. Has only non-static data members that are of standard-layout type
2. Has the same access control (public, private, protected) for all non-static members
3. Has no virtual functions
4. Has no virtual base classes
5. Has only base classes that are of standard-layout type
6. Has no bases classes of the same type as the first defined non-static member
7. Either has no base classes with non-static members, or has no non-static data members in the most derived class and at most one base class with non-static members. In essence, there may be only one class in this classes hierarchy that has non-static members.