c++ - Do default constructors need to call base class default constructors? -


was reading this answer , surprised me, suggestion must always call base class constructor in derived class constructor. if working default constructors, consider:

class bar : public foo { private: int y;  public: bar() : foo(), y(0) { }  ...

is call foo() necessary here?

you not need explicitly call base class constructor in constructor, in case compiler implicitly calls default constructor, or compile-time error, if none callable.
same applies members non-pod.

an alternative member initialiser list only consisting of delegation constructor of class, creating delegating constructor.


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