An iterator has turned implicitly into a typename...

[YourSurrogateGod]

I'm using gcc. Ok, in file graph.cpp, on line 56 I got the below warnings...

g++ -g -c graph.cpp
graph.cpp: In member function `bool
   graph<T>::search_list(std::basic_string<char, std::char_traits<char>,
   std::allocator<char> >)':
graph.cpp:56: warning: `std::list<graph<T>::graph_node,
   std::allocator<graph<T>::graph_node> >::iterator' is implicitly a typename
graph.cpp:56: warning: implicit typename is deprecated, please see the
   documentation for details
g++ main.o graph.o -o main

Why am I getting these warnings? All I did was make an iterator and from a list.