why gcc-4.9.2 can't support std::string.insert(iterator, range) to return iterator

According to here, c++11 should support:

template< class InputIt >
iterator insert( const_iterator pos, InputIt first, InputIt last );

But when I try to compile following codes by g++ 4.9.2:

std::string str{ "hello world" }, addition{ "h my" };
auto iter = str.erase(str.begin(), str.begin() + 4);
iter = str.insert(next(iter), addition.begin(), addition.end()); // Error

Error:

error: no match for 'operator=' (operand types are '__gnu_cxx::__normal_iterator<char*, std::basic_string<char> >' and 'void')
 iter = str.insert(next(iter), addition.begin(), addition.end());
      ^

However, Visual Studio 2013 and Clang seem no problem.