pure virtual functions and name injection

[Jérôme Cornet]

Hello,

i saw this message here on the mailing list archive:

http://gcc.gnu.org/ml/gcc-help/2006-03/msg00027.html

and followed the thread with great interest.

John Love-Jensen wrote:

> > The two functions have different prototypes, I thought that the  
> compiler was
> able to differentiate them.
>
> Different prototypes, but the same name.  The name is what is  
> causing the
> error, not the rest of the signature.

Ok, i guess this is because of the same name, but why is it ok with  
the C++ standard?

operator++(int) and operator++() do have the same name, but they are  
considered
as different by a c++ compiler...

> To avoid this kind of situation, I recommend using a different  
> method name
> for the method with the different signature.
>
> >Then it compiles but there is a *link* error !  Can somebody  
> explain me what
> happens ?
>
> You have not defined the a::foo function anywhere.  So there is a link
> error.

Technically, a::foo() is not "defined" anywhere (i understand what  
you mean),
but it does not need to, since it is a pure virtual functions.
But a::foo() is "implemented" in class "d" (return 1), so when  
calling a::foo() the
compiler should redirect the call to the implementation d::foo(), no?

jérôme cornet