Hi John, John Love-Jensen wrote: > [...] > In C++, a copy constructor is a const reference. Hmm, I would say *usually* it is a const reference.-- But eventually it is not, like in my case or in the case of std::auto_ptr. Of course you could say this isn't a copy constructor because it doesn't take a const reference. But I think it is anyway because it still has the semantic of a copy operation. Anyway, I need to have a constructor taking a non-const reference which g++ doesn't allow. And I still don't know why g++ is acting this way here and how to work around it. Yours, Christian > [...]