Generic function dispatch mechanism

I am trying to write a generic function dispatch mechanism where I do some additional work before calling the actual function (e.g. time the function's execution). The following code works, except for functions of the type void f(....) since we are declaring ret.

#define execute(fn, ...)    exec_helper(#fn, fn, ##__VA_ARGS__)
#define execute0(fn)        exec_helper(#fn, fn)

template <typename TASK, typename... ARGS>
auto exec_helper(const char *fn_name, TASK&& task, ARGS&&... args)
{
      //std::function<std::result_of_t<TASK(ARGS...)> ()> func
      //           = std::bind(std::forward<TASK>(task),
      //                       std::forward<ARGS>(args)...);

#ifdef TIME_FUNC
      auto start = std::chrono::steady_clock::now();
#endif

      auto ret = task(std::forward<ARGS>(args)...);

#ifdef TIME_FUNC
      auto end = std::chrono::steady_clock::now();
      auto diff = end - start;
      auto time = std::chrono::duration<double, std::milli>(diff).count();
      std::cout << "\n" << fn_name << "\t = "
                << std::setprecision(3) << time << " ms\n";
#endif

      return ret;
}

Is there a way to make it work for these type of functions as well? Perhaps using some template tricks?