http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45942
--- Comment #10 from Jonathan Wakely <redi at gcc dot gnu.org> 2010-10-08 15:59:08 UTC --- (In reply to comment #9) > > I really tried everything, but I have to admit I missed that one. Sorry. But > you have to admit that it is a rather unnatural way to make friends. > Furthermore, the third parameter Z is missing (I would prefer A<X,Y>&Z), but > that does not seem to be a problem for the compiler. You can just add it if it makes you feel better. That parameter isn't used in the friend declaration, so giving it a name is optional. YOu can call it Z or whatever you want, it doesn't matter. > Thus it seems that the bug is that c++ is designed is such a way that it gives > error messages which are incorrect. C++ doesn't specify the text of error messages, it says what is valid and what is not. The compiler rejected your code because it's not valid. I don't know why you think the error message is incorrect. This is a template declaration: template <classA &instanceA> friend class classB; It has one parameter. classB was already declared as a template with three parameters. So you get this error message: pr45942.cc:9:45: error: redeclared with 1 template parameter pr45942.cc:3:57: note: previous declaration ‘template<class T, int C, classA<T, C>& instanceA> class classB’ used 3 template parameters That seems correct to me. > If you would have followed the title of my bug report immediately instead of > saying that is was invalid, then the discussion would have been unnecessary. But your bug report IS invalid. I repeat, you said there was a bug in the compiler, I said there isn't. If you had said "please help me fix my code" that would have been a different discussion (and you'd have been asked to go somewhere else, like a C++ forum or newsgroup) Despite that, you have succeeded in turning it into a discussion of why your code is not valid. > Now it is still odd that the first attempt gives an error so lately. The > template precompiler counts three arguments and the template instantiator > counts one, which is not very consistent. There's no "template precompiler" Please take this somewhere else, GCC's bugzilla is not the place for it.
