线程构造函数周围的variadic模板包装无法编译

我正在尝试编译以下程序。

#include <iostream>
#include <thread>

struct State
{
    State (std::string message) : message (message)
    {
    }

    template <class Function, class... Args>
    void
    spawn (Function&& function, Args&&... args)
    {
        std::thread t (&State::run <Function, Args...>, this, function, args...);
        t . join ();
    }

    template <class Function, class... Args>
    void
    run (Function&& function, Args&&... args)
    {
        std::cout << this -> message << std::endl;
        function (args...);
    }

    ~State () = default;

    std::string message;
};

void
print (std::string message)
{
    std::cout << message << std::endl;
}

int main (int argc, char ** argv)
{
    State state ("Hello, World!\n");

    state.spawn (print, "Goodbye, World!\n");

    return 0;
}

当我尝试使用clang 6.0.1编译它时,我得到了以下输出。

$ clang++ main.cpp
In file included from main.cpp:2:
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/8.2.0/../../../../include/c++/8.2.0/thread:242:40: error: 
      no matching member function for call to '_M_invoke'
        -> decltype(std::declval<_Invoker&>()._M_invoke(_Indices()))
                    ~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/8.2.0/../../../../include/c++/8.2.0/thread:127:8: note: 
      in instantiation of template class
      'std::thread::_Invoker<std::tuple<void (State::*)(void
      (&)(std::__cxx11::basic_string<char>), char const (&)[17]), State *,
      void (*)(std::__cxx11::basic_string<char>), const char *> >'
      requested here
              __make_invoker(std::forward<_Callable>(__f),
              ^
main.cpp:14:15: note: in instantiation of function template specialization
      'std::thread::thread<void (State::*)(void
      (&)(std::__cxx11::basic_string<char>), char const (&)[17]), State *,
      void (&)(std::__cxx11::basic_string<char>), char const (&)[17]>'
      requested here
                std::thread t (&State::run <Function, Args...>, thi...
                            ^
main.cpp:41:8: note: in instantiation of function template specialization
      'State::spawn<void (&)(std::__cxx11::basic_string<char>), char const
      (&)[17]>' requested here
        state.spawn (print, "Goodbye, World!\n");
              ^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/8.2.0/../../../../include/c++/8.2.0/thread:231:4: note: 
      candidate template ignored: substitution failure [with _Ind = <0, 1,
      2, 3>]: no matching function for call to '__invoke'
          _M_invoke(_Index_tuple<_Ind...>)
          ^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/8.2.0/../../../../include/c++/8.2.0/thread:186:13: error: 
      type 'std::thread::_Invoker<std::tuple<void (State::*)(void
      (&)(std::__cxx11::basic_string<char>), char const (&)[17]), State *,
      void (*)(std::__cxx11::basic_string<char>), const char *> >' does not
      provide a call operator
        _M_run() { _M_func(); }
                   ^~~~~~~
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/8.2.0/../../../../include/c++/8.2.0/thread:182:2: note: 
      in instantiation of member function
      'std::thread::_State_impl<std::thread::_Invoker<std::tuple<void
      (State::*)(void (&)(std::__cxx11::basic_string<char>), char const
      (&)[17]), State *, void (*)(std::__cxx11::basic_string<char>), const
      char *> > >::_M_run' requested here
        _State_impl(_Callable&& __f) : _M_func(std::forward<_Callab...
        ^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/8.2.0/../../../../include/c++/8.2.0/thread:197:24: note: 
      in instantiation of member function
      'std::thread::_State_impl<std::thread::_Invoker<std::tuple<void
      (State::*)(void (&)(std::__cxx11::basic_string<char>), char const
      (&)[17]), State *, void (*)(std::__cxx11::basic_string<char>), const
      char *> > >::_State_impl' requested here
        return _State_ptr{new _Impl{std::forward<_Callable>(__f)}};
                              ^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/8.2.0/../../../../include/c++/8.2.0/thread:126:25: note: 
      in instantiation of function template specialization
      'std::thread::_S_make_state<std::thread::_Invoker<std::tuple<void
      (State::*)(void (&)(std::__cxx11::basic_string<char>), char const
      (&)[17]), State *, void (*)(std::__cxx11::basic_string<char>), const
      char *> > >' requested here
        _M_start_thread(_S_make_state(
                        ^
main.cpp:14:15: note: in instantiation of function template specialization
      'std::thread::thread<void (State::*)(void
      (&)(std::__cxx11::basic_string<char>), char const (&)[17]), State *,
      void (&)(std::__cxx11::basic_string<char>), char const (&)[17]>'
      requested here
                std::thread t (&State::run <Function, Args...>, thi...
                            ^
main.cpp:41:8: note: in instantiation of function template specialization
      'State::spawn<void (&)(std::__cxx11::basic_string<char>), char const
      (&)[17]>' requested here
        state.spawn (print, "Goodbye, World!\n");
              ^
2 errors generated.

我不知道我做错了什么。我可以说编译器似乎不喜欢我传递给线程对象的第一个参数,但是我不知道为什么或者如何修复它。

我尝试将函数从成员函数引用更改为静态成员函数引用(添加结构指针作为附加参数)。这对产量没有实质性影响。

我还尝试用gcc编译它,看看它是否能告诉我一些有趣的事情。这似乎和Clang的代码有同样的问题,但是输出对我来说更冗长,也同样不轻松。

为什么我的程序不能编译?此错误消息试图告诉我什么?