Problem accessing base member in derived constructor

Question

Given the following classes:

class Foo
{
    struct BarBC
    {
    protected:
        BarBC(uint32_t aKey)
            : mKey(aKey)
              mOtherKey(         


        

Answer 1

You can't initialize members of a base class through a member initializer list, only direct and virtual base classes and non-static data members of the class itself.
Pass additional parameters to the base class' constructor instead:

struct BarBC {
    BarBC(uint32_t aKey, uint32_t otherKey = 0)
      : mKey(aKey), mOtherKey(otherKey)
    {}
    // ...
};

struct Bar : public BarBC {
    Bar(uint32_t aKey, uint32_t aOtherKey)
      : BarBC(aKey, aOtherKey)
    {}
};

Answer 2

You can't do this as BarBC constructs the mOtherKey - you can't override it.

You have either assign new value:

Bar(...) : ...
{ mOtherKey=aOtherKey; }

Or create additional BarBC constructor that has a parameter of mOtherKey