On Wed, Sep 20, 2023 at 3:50 PM Vladimir Grigoriev via Std-Discussion <
std-discussion_at_[hidden]> wrote:

> In the section "11.9 Member access control" of the C++20 Standard there is
> provided an example (p.#7, example #2) of using a protected inner class of
> a class as a base class for a derived class and the corresponding text
> relative to such a declaration.
>
> Here is a simplified by me version of the example
>
> class A {//...protected:
> struct B { };
> };
> struct D: A::B, A { };
>
> And there is written
>
> Similarly, the use of A::B as a base-specifier is well-formed because D is
> derived from A, so checking of base-specifiers must be deferred until the
> entire base-specifier-list has been seen.
>
> However this declaration
>
> struct D: A::B, A { };
>
> is compiled by neither for example x86-64 clang (trunk) nor by MS VS C++ w
> ith its last version of the compiler.
>
> if to change the declaration like
>
> struct D: A, A::B { };
>
> then the MS VS C++ compiler compiles the declaration. However the
> compiler x86-64 clang (trunk) still does not compile the declaration.
>
> is it a bug of the compilers?
>

It seems that the standard is pretty explicit here about the intent, so
it's a compiler bug.


>
> With best regards,
> (Vlad from Moscow)
>
> You can meet me at http://cpp.forum24.ru/ or www.stackoverflow.com or
> http://ru.stackoverflow.com
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-- 
*Brian Bi*