Compiler Error C2875

using-declaration causes a multiple declaration of 'class::identifier'

The declaration causes the same item to be defined twice.

This error is obsolete in Visual Studio 2022 and later versions.

The following sample generates C2875:

// C2875.cpp
struct A {
   void f(int*);
};

struct B {
   void f(double*);
};

struct AB : A, B {
   using A::f;
   using A::f;   // C2875
   using B::f;
};