C++ sizeof wrapper class

Question

Suppose I have a class A that does not inherit from anything, has no virtual methods, and has exactly one variable of type T. Does C++ guarantee sizeof(A) == sizeof(T)

Answer 1

I think C++ should guarantee sizeof(A) == sizeof(T).

Consider bellow situation, C++ should make it works just like in C:

A a[10];
T t[10];

A * ap = (A *) t;
T * tp = (T *) a;

memcpy(ap, tp, sizeof(*ap));