Compiler Error C2385

ambiguous access of 'member'

A member is inherited from more than one base type, making unqualified access to that member ambiguous. To resolve this error:

• Explicitly qualify access to the member.
• Cast the object to the base class containing the member before accessing the member.
• Rename the ambiguous member in the base class.
• Bring the member into scope.

Example

The following sample generates C2385:

// C2385.cpp
struct A
{
    void func1(int i) {}
    void func2() {}
};

struct B
{
    void func1(char c) {}
    void func2() {}
};

struct C : A, B
{
    // Uncomment the following lines to resolve the first 2 errors
    // The error below for the call to c.func2() will remain
    // using A::func1;
    // using B::func1;
};

int main()
{
    C c;

    c.func1(123); // C2385
    c.func1('a'); // C2385
    c.func2(); // C2385

    c.A::func2(); // OK because explicitly qualified
    c.B::func2(); // OK because explicitly qualified
    static_cast<A>(c).func2(); // OK because of the cast
    static_cast<B>(c).func2(); // OK because of the cast
}

You can resolve the ambiguous calls to func1 by bringing both overloads into scope. However, this doesn't work for func2 because A::func2 and B::func2 don't take arguments, so calling them can't be differentiated by their parameters. You can resolve the issue by:

• Introduce the one you want to use into scope
• Explicitly qualify the call with the base type
• Cast the object before calling the function.