[patch] fix c++ compilation warnings and test cases

[Andreas Tobler]

Tom Tromey wrote:
>>>>>> "Andreas" == Andreas Tobler <toa@pop.agri.ch> writes:
> 
> Andreas> Right now all *.cc testcases fail due to the ? redundant ?
> Andreas> declarations in Class.h. Also the compilation of the *.cc
> Andreas> source files spits this warning:
> 
> It seems to me that declarations which are merely redundant shouldn't
> cause a warning, unless we have some -W asking for a warning (I didn't
> look).

We build with -Wextra -Wall ;)

Makefile.am:WARNINGS = -Wextra -Wall

> Andreas> Tom, does the // Friend classes comment only belong to the
> Andreas> declarations I'd like to remove or also to the following ones?
> 
> It is ok to delete the comment.
> 
> Andreas> Ok for main?
> 
> Yes.  Thanks.

I'll commit if regtest has succeeded.

Thanks,
Andreas