Does it matter where is the inline keyword is specified, base class, derived class or both?

Question

Suppose we wan't to hint the compiler to inline member function where applicable.

class Base
{
 public:
      inline virtual f() = 0;
};

class Derived : public Base
{
 public:
      virtual f() override; // no inline specifier here
};

Do I need to specify inline in Derived::f() or can I omit the keyword and be sure that virtual Derived::f() is the same thing as inline Derived::f() ?

I mean is the inline keyword implicitly specified for Derived::f() or do I need to explicitly type it once again?

Answer 1

Do I need to specify inline in Derived::f() or can I omit the keyword and be sure that virtual Derived::f() is the same thing as inline Derived::f() ?

If you omit the inline keyword in the derived class, it is not inline in the derived class.

I mean is the inline keyword implicitly specified for Derived::f()

No, it is not.

or do I need to explicitly type it once again?

Yes, you do. However, a compiler will most likely generate code for it as though it is a non-inline member function since it is a virtual member function.