> > and
> >         o neither non-C++ libraries, nor any other code should
> >           include c++rt0.o
> 
> Do you mean that g++ should be relied on to include c++rt0.o when
> necessary? If not I don't understand what you mean here - sorry for
> being thick.

You only need c++rt0.o when building a (a.out) shared library from C++ code.
It takes care of calling static constructors/destructors in that library
when it is loaded into a program.

-pk