That's just how C++ is designed/defined, any book on C++ should be able to explain this in more detail.Since it was not a bug, I have posted related questions on the gcc- help list, and I have had valuable answers.
http://gcc.gnu.org/ml/gcc-help/2006-03/msg00026.html
Now I have understood :-) Thanks for taking the time to answer ! Regards, Pierre Chatelier
