Is this a bug in GCC with private non-type template parameters?

[Renegat]

Hello everybody,

do you agree that the following template related problem is a bug in the g++ front-end of GCC?

If someone with a GCC bugzilla account thinks so, maybe he can submit a bug report there (the automatic account creation has been restricted now).

Thanks.

/*
Product: gcc
Comp: c++
Versions: 11.4 / 12.3 / 13.1 (all currently supported)

Summary: False access error for non-type template parameter of a nested class

Keywords: rejects-valid, accepts-invalid
*/

//
// The out-of-class definition of a nested class member template with a
// private non-type template parameter triggers a false compilation error
//
class A
{
enum e{ E };

template <A::e T>
struct class_template;
};

// BUG #1: This definition outside the class body is valid, but g++ aborts
// the compilation with an error: ‘enum A::e’ is private within this context’
template <A::e T>
struct A::class_template
{
};

// Maybe helpful for a bug fix:
// The compilation error is not triggered for a similar class with a member
// function template defined outside the class body
class B
{
enum e{ E };

template <B::e T>
void function_template();
};

// g++ compiles fine for a function template :
template <B::e T>
void B::function_template()
{
}

// BUG #2: g++ compiles this without any error, but ‘B::e’ is private within
// this context
template <B::e T>
void global_function_template()
{
}

// No BUG here: For a similar class template the g++ compiler correctly reports
// a compilation error (‘enum B::e’ is private within this context)
template <B::e T>
class global_class_template
{
};