错误：没有匹配的 function 调用 'std::thread::_Invoker <std::tuple< div><div id="text_translate"><p> 我正面临线程问题。</p><p> 我试图在 Chronometer class 的线程内执行 function，包括一个 while 循环：</p><p> 这是部分代码：</p><pre> for(int i = 0; i<car_data.size();i++) { if(car_data[i]->checkArea(frame, pt1_zone, pt2_zone)) { std::thread(&Chronometer::start_chrono, car_crono[i], std::ref(chrono)); cv::rectangle(frame, car_data[i]->pt1, car_data[i]->pt2, cv::Scalar(255,0,0), 1, cv::LINE_8,0); //cv::putText(frame, "Parked", car_data[i]->pt1, cv::FONT_HERSHEY_DUPLEX, 0.9, cv::Scalar( 50, 255, 50 )); //occupancy_state = place.occupancyTrue(); //place_1.occupancy = true;</pre><p> car_crono 和 chrono 的类型</p><pre>std::vector<Chronometer*> car_crono; Chronometer chrono;</pre><p> 这是我的 class 计时器：</p><pre> class Chronometer { private: static int hour, min, sec; //std::stringstream ss; //Chronometer chrono; public: Chronometer(); static Chronometer& start_chrono(Chronometer& chrono); static Chronometer& finish_chrono(Chronometer& chrono); friend std::ostream& operator<<(std::ostream& flux, Chronometer t); Chronometer& operator=(const Chronometer& other); ~Chronometer(); };</pre><p> 对于线程，我尝试了几种参数。 最后一个：</p><pre> std::thread(&Chronometer::start_chrono, car_crono[i], std::ref(chrono));</pre><p> 我猜 ref 是必要的，但没有改变。</p><p> 这是完整的错误</p><pre>/usr/include/c++/7/thread: In instantiation of 'struct std::thread::_Invoker<std::tuple<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> > >': /usr/include/c++/7/thread:127:22: required from 'std::thread::thread(_Callable&&, _Args&&...) [with _Callable = Chronometer& (*)(Chronometer&); _Args = {Chronometer*&, std::reference_wrapper<Chronometer>}]' recognizer_rtsp.cxx:348:76: required from here /usr/include/c++/7/thread:240:2: error: no matching function for call to 'std::thread::_Invoker<std::tuple<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> > >::_M_invoke(std::thread::_Invoker<std::tuple<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> > >::_Indices)' operator()() ^~~~~~~~ /usr/include/c++/7/thread:231:4: note: candidate: template<long unsigned int..._Ind> decltype (std::__invoke((_S_declval<_Ind>)()...)) std::thread::_Invoker<_Tuple>::_M_invoke(std::_Index_tuple<_Ind...>) [with long unsigned int..._Ind = {_Ind...}; _Tuple = std::tuple<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> >] _M_invoke(_Index_tuple<_Ind...>) ^~~~~~~~~ /usr/include/c++/7/thread:231:4: note: template argument deduction/substitution failed: /usr/include/c++/7/thread: In substitution of 'template<long unsigned int..._Ind> decltype (std::__invoke(_S_declval<_Ind>()...)) std::thread::_Invoker<std::tuple<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> > >::_M_invoke<_Ind...>(std::_Index_tuple<_Ind1...>) [with long unsigned int..._Ind = {0, 1, 2}]': /usr/include/c++/7/thread:240:2: required from 'struct std::thread::_Invoker<std::tuple<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> > >' /usr/include/c++/7/thread:127:22: required from 'std::thread::thread(_Callable&&, _Args&&...) [with _Callable = Chronometer& (*)(Chronometer&); _Args = {Chronometer*&, std::reference_wrapper<Chronometer>}]' recognizer_rtsp.cxx:348:76: required from here /usr/include/c++/7/thread:233:29: error: no matching function for call to '__invoke(std::__tuple_element_t<0, std::tuple<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> > >, std::__tuple_element_t<1, std::tuple<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> > >, std::__tuple_element_t<2, std::tuple<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> > >)' -> decltype(std::__invoke(_S_declval<_Ind>()...)) ~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~ In file included from /usr/include/c++/7/tuple:41:0, from /usr/include/c++/7/bits/stl_map.h:63, from /usr/include/c++/7/map:61, from../alpr_utils.h:7, from recognizer_rtsp.cxx:34: /usr/include/c++/7/bits/invoke.h:89:5: note: candidate: template<class _Callable, class... _Args> constexpr typename std::__invoke_result<_Functor, _ArgTypes>::type std::__invoke(_Callable&&, _Args&&...) __invoke(_Callable&& __fn, _Args&&... __args) ^~~~~~~~ /usr/include/c++/7/bits/invoke.h:89:5: note: template argument deduction/substitution failed: /usr/include/c++/7/bits/invoke.h: In substitution of 'template<class _Callable, class... _Args> constexpr typename std::__invoke_result<_Functor, _ArgTypes>::type std::__invoke(_Callable&&, _Args&&...) [with _Callable = Chronometer& (*)(Chronometer&); _Args = {Chronometer*, std::reference_wrapper<Chronometer>}]': /usr/include/c++/7/thread:233:29: required by substitution of 'template<long unsigned int..._Ind> decltype (std::__invoke(_S_declval<_Ind>()...)) std::thread::_Invoker<std::tuple<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> > >::_M_invoke<_Ind...>(std::_Index_tuple<_Ind1...>) [with long unsigned int..._Ind = {0, 1, 2}]' /usr/include/c++/7/thread:240:2: required from 'struct std::thread::_Invoker<std::tuple<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> > >' /usr/include/c++/7/thread:127:22: required from 'std::thread::thread(_Callable&&, _Args&&...) [with _Callable = Chronometer& (*)(Chronometer&); _Args = {Chronometer*&, std::reference_wrapper<Chronometer>}]' recognizer_rtsp.cxx:348:76: required from here /usr/include/c++/7/bits/invoke.h:89:5: error: no type named 'type' in 'struct std::__invoke_result<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> >'</pre><p> 我应该通过线程传递什么样的参数？</p><p> 我去了几个链接来寻找解决方案，但没有什么能解决我的问题：</p><p> <a href="https://stackoverflow.com/questions/21048906/stdthread-pass-by-reference-calls-copy-constructor" rel="nofollow noreferrer">std::thread 通过引用传递调用复制构造函数</a></p><p> <a href="https://stackoverflow.com/questions/67625058/no-matching-function-to-invoke-using-stdthread" rel="nofollow noreferrer">没有匹配的 function 调用，使用 std::thread</a></p><p> ... </p></div></std::tuple<>

Question

I'm facing a thread problem.

I tried to execute function inside a thread from Chronometer class including a while loop:

Here is the part code:

for(int i = 0; i<car_data.size();i++)
            {
                if(car_data[i]->checkArea(frame, pt1_zone, pt2_zone))
                {
                    std::thread(&Chronometer::start_chrono, car_crono[i], std::ref(chrono));                            
                    cv::rectangle(frame, car_data[i]->pt1, car_data[i]->pt2, cv::Scalar(255,0,0), 1, cv::LINE_8,0);
                    //cv::putText(frame, "Parked", car_data[i]->pt1, cv::FONT_HERSHEY_DUPLEX, 0.9, cv::Scalar( 50, 255, 50 ));
                    //occupancy_state = place.occupancyTrue();
                    //place_1.occupancy = true;

The type of car_crono and chrono

std::vector<Chronometer*> car_crono;
Chronometer chrono;

Here is my class Chronometer:

class Chronometer
{
    private:
        static int hour, min, sec;
        //std::stringstream ss;
        //Chronometer chrono;

    public:

        Chronometer();
        static Chronometer& start_chrono(Chronometer& chrono);
        static Chronometer& finish_chrono(Chronometer& chrono);
        friend std::ostream& operator<<(std::ostream& flux, Chronometer t);
        Chronometer& operator=(const Chronometer& other);
        ~Chronometer();

};

For the thread I tried several kind of parameters. The last one:

std::thread(&Chronometer::start_chrono, car_crono[i], std::ref(chrono));        

I guessed a ref was necessary but doesn't change.

Here is the full error

/usr/include/c++/7/thread: In instantiation of ‘struct std::thread::_Invoker<std::tuple<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> > >’:
/usr/include/c++/7/thread:127:22:   required from ‘std::thread::thread(_Callable&&, _Args&& ...) [with _Callable = Chronometer& (*)(Chronometer&); _Args = {Chronometer*&, std::reference_wrapper<Chronometer>}]’
recognizer_rtsp.cxx:348:76:   required from here
/usr/include/c++/7/thread:240:2: error: no matching function for call to ‘std::thread::_Invoker<std::tuple<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> > >::_M_invoke(std::thread::_Invoker<std::tuple<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> > >::_Indices)’
  operator()()
  ^~~~~~~~
/usr/include/c++/7/thread:231:4: note: candidate: template<long unsigned int ..._Ind> decltype (std::__invoke((_S_declval<_Ind>)()...)) std::thread::_Invoker<_Tuple>::_M_invoke(std::_Index_tuple<_Ind ...>) [with long unsigned int ..._Ind = {_Ind ...}; _Tuple = std::tuple<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> >]
    _M_invoke(_Index_tuple<_Ind...>)
    ^~~~~~~~~
/usr/include/c++/7/thread:231:4: note:   template argument deduction/substitution failed:
/usr/include/c++/7/thread: In substitution of ‘template<long unsigned int ..._Ind> decltype (std::__invoke(_S_declval<_Ind>()...)) std::thread::_Invoker<std::tuple<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> > >::_M_invoke<_Ind ...>(std::_Index_tuple<_Ind1 ...>) [with long unsigned int ..._Ind = {0, 1, 2}]’:
/usr/include/c++/7/thread:240:2:   required from ‘struct std::thread::_Invoker<std::tuple<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> > >’
/usr/include/c++/7/thread:127:22:   required from ‘std::thread::thread(_Callable&&, _Args&& ...) [with _Callable = Chronometer& (*)(Chronometer&); _Args = {Chronometer*&, std::reference_wrapper<Chronometer>}]’
recognizer_rtsp.cxx:348:76:   required from here
/usr/include/c++/7/thread:233:29: error: no matching function for call to ‘__invoke(std::__tuple_element_t<0, std::tuple<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> > >, std::__tuple_element_t<1, std::tuple<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> > >, std::__tuple_element_t<2, std::tuple<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> > >)’
    -> decltype(std::__invoke(_S_declval<_Ind>()...))
                ~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
In file included from /usr/include/c++/7/tuple:41:0,
                 from /usr/include/c++/7/bits/stl_map.h:63,
                 from /usr/include/c++/7/map:61,
                 from ../alpr_utils.h:7,
                 from recognizer_rtsp.cxx:34:
/usr/include/c++/7/bits/invoke.h:89:5: note: candidate: template<class _Callable, class ... _Args> constexpr typename std::__invoke_result<_Functor, _ArgTypes>::type std::__invoke(_Callable&&, _Args&& ...)
     __invoke(_Callable&& __fn, _Args&&... __args)
     ^~~~~~~~
/usr/include/c++/7/bits/invoke.h:89:5: note:   template argument deduction/substitution failed:
/usr/include/c++/7/bits/invoke.h: In substitution of ‘template<class _Callable, class ... _Args> constexpr typename std::__invoke_result<_Functor, _ArgTypes>::type std::__invoke(_Callable&&, _Args&& ...) [with _Callable = Chronometer& (*)(Chronometer&); _Args = {Chronometer*, std::reference_wrapper<Chronometer>}]’:
/usr/include/c++/7/thread:233:29:   required by substitution of ‘template<long unsigned int ..._Ind> decltype (std::__invoke(_S_declval<_Ind>()...)) std::thread::_Invoker<std::tuple<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> > >::_M_invoke<_Ind ...>(std::_Index_tuple<_Ind1 ...>) [with long unsigned int ..._Ind = {0, 1, 2}]’
/usr/include/c++/7/thread:240:2:   required from ‘struct std::thread::_Invoker<std::tuple<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> > >’
/usr/include/c++/7/thread:127:22:   required from ‘std::thread::thread(_Callable&&, _Args&& ...) [with _Callable = Chronometer& (*)(Chronometer&); _Args = {Chronometer*&, std::reference_wrapper<Chronometer>}]’
recognizer_rtsp.cxx:348:76:   required from here
/usr/include/c++/7/bits/invoke.h:89:5: error: no type named ‘type’ in ‘struct std::__invoke_result<Chronometer& (*)(Chronometer&), Chronometer*, std::reference_wrapper<Chronometer> >’

What kind of parameter should I pass through the thread?

I went to several links to find a solution but nothing could solve my problem:

std::thread pass by reference calls copy constructor

No matching function to invoke, using std::thread

...

Answer 1

Chronometer::start_chrono is a static function, so it's not bound to any object, ie doesn't need an object to called upon.

Static member functions are not associated with any object. When called, they have no this pointer.

You should have simply written.

std::thread(&Chronometer::start_chrono, std::ref(chrono));