Exemplo

class MyClass {
public:
MyClass (char *nameInput, int twoInput, int threeInput);
private:
char *one;
int two, three;
int four;
};

MyClass::MyClass (char *nameInput, int twoInput, int threeInput) : two(twoInput), one(nameInput), three(threeInput), four(twoInput + threeInput)
{
}

Solução

Inicialize membros de classe na mesma ordem em que eles são declarados.

class MyClass {
public:
MyClass (char *nameInput, int twoInput, int threeInput);
private:
char *one;
int two, three;
int four;
};

MyClass::MyClass (char *nameInput, int twoInput, int threeInput) : one(nameInput), two(twoInput), three(threeInput), four(twoInput + threeInput)
{
}