obsolete C++ constructor initialization syntax
A direct base class was not named in the constructor.
The new-style initialization list for a constructor member requires each direct base class to be explicitly named, even if it is the only base class in the list.
The following is an example of this error:
class B
{
public:
B();
B( int );
};
class D : public B
{
public:
D( int i ) : ( i ) {} // error, B was not named
D( int i ) : B( i ) {} // OK
};