In all C++ object layouts, I have seen that members follow the previous one
as in a C structure.

My main point is that hackers/bad people can take advantage of this.

Regards,
Amit



On Mon, Feb 17, 2025, 3:17 PM Jan Schultke <janschultke_at_[hidden]>
wrote:

> Your code has undefined behavior because you cannot obtain your j_ptr
> by doing i_ptr + 1. A past the end pointer is not a pointer to the
> next member.
>
> However, the example is correct without j_ptr. It is possible to
> obtain a pointer to the first member of a standard-layout class such
> as MyClass, even if that member is private.
>
> I wouldn't really call it a security hole. The only way you will do
> this in idiomatic C++ code is with reinterpret_cast, and
> reinterpret_cast is a giant red flag which says "I'm an expert, I know
> what I'm doing, and what I'm doing is potentially dangerous". This
> never happens by accident.
>