std::thread taking lambda with ref arg fails to compile

I'm reading C++ concurrency in action. Chapter 2.4 describes a parallell_accumulate algorithm.

I tried - as a learning experiment - to replace the functor used there, with a generic lambda.

I've distilled the compilation error down to:

#include <thread>

template <typename T>
struct f {
    void operator() (T& result) { result = 1;}
};

int main() {
    int x = 0;
    auto g = [](auto& result) { result = 1; };

    std::thread(f<int>(), std::ref(x));  // COMPILES
    std::thread(g, std::ref(x));         // FAILS TO COMPILE
}

The error message:

 In file included from /usr/include/c++/4.9/thread:39:0,
                 from foo.cpp:1:
/usr/include/c++/4.9/functional: In instantiation of ‘struct std::_Bind_simple<main()::<lambda(auto:1&)>(std::reference_wrapper<int>)>’:
/usr/include/c++/4.9/thread:140:47:   required from ‘std::thread::thread(_Callable&&, _Args&& ...) [with _Callable = main()::<lambda(auto:1&)>&; _Args = {std::reference_wrapper<int>}]’
foo.cpp:13:31:   required from here
/usr/include/c++/4.9/functional:1665:61: error: no type named ‘type’ in ‘class std::result_of<main()::<lambda(auto:1&)>(std::reference_wrapper<int>)>’
       typedef typename result_of<_Callable(_Args...)>::type result_type;
                                                             ^
/usr/include/c++/4.9/functional:1695:9: error: no type named ‘type’ in ‘class std::result_of<main()::<lambda(auto:1&)>(std::reference_wrapper<int>)>’
         _M_invoke(_Index_tuple<_Indices...>)
         ^

My compiler version

$ g++ --version
g++ (Ubuntu 4.9.1-16ubuntu6) 4.9.1

Why do the compilation fail for the lambda but not the functor?