c++ - 下面[class.derived]/7中突出显示的 “of the same type”表达式是什么意思？

Question

[class.derived]/7:

[Note: A base class subobject might have a layout ([basic.stc])different from the layout of a most derived object of the sametype. A base class subobject might have a polymorphic behavior([class.cdtor]) different from the polymorphic behavior of a mostderived object of the same type. A base class subobject may be ofzero size ([class]); however, two subobjects that have the same classtype and that belong to the same most derived object must not beallocated at the same address ([expr.eq]). — end note]

Answer 1

struct B { /* ... */ };
struct D : B { /* ... */ };

B b;
D d;

B的基类子对象 d的布局可能与相同类型( b)的最派生对象(此处为 B)不同。例如，一个实现可以为 B的成员重用 D的尾部填充。