Bug in example in 13.5.4, namespaces/using static directives

[RexJaeschke]

The final example in this section has a bug:

namespace N1 
{
    static class A 
    {
        public static void M(string s){}
    }

    static class B : A
    {
        public static void M2(string s){}
    }
}

namespace N2
{
    using static N1.B;

    class C
    {
        void N()
        {
            M2("B");      // OK, calls B.M2
            M("C");       // Error. M unknown 
        }
    }
}

Based on the comment near the end, the intent is that an error results based on M being unknown. However, the compiler doesn't get that far. Instead, it complains about the declaration

static class B : A

According to 14.2.2.4.1, a static class (such as A) cannot be used as a base class, and a static class (such as B) cannot derive from anything other than object. So, the program is ill-formed.

Blame says this example was added in July 2021, in V6.

I didn't see an obvious workaround.

[RexJaeschke]

This was resolved by removing static from both classes.

[KalleOlaviNiemitalo]

Same as #689.