Hi David, On Fri, Oct 16, 2009 at 10:58:33AM -0700, daviddoria wrote: > > With this code: > http://www.rpi.edu/~doriad/Daniweb/maxflow/ > If I run > > g++ Example.cpp graph.cpp > > with g++ 3.3, everything works fine. However if I run the same command with > g++ 4.4, I get this error: > > Example.cpp:(.text+0x38): undefined reference to `Graph<int, int, > int>::Graph(int, int, void (*)(char*))' as far as I understand the C++ - standard, the statement "template class Graph<int,int,int>;" does define the class "Graph<int,int,int>" and declare all member functions. However, it does NOT define the member functions of Graph<init,int,int>. > Does anyone know how I can get this to work with g++ 4.4? If you explicitely instantiate the template member function, it will work: template class Graph<int,int,int>::Graph(int, int, void (*)(char *)); (Besides: your code does not compile - "NULL" is not defined, you should a e.g. #include <cstdlib> :-) HTH, Axel
