C2672 "invoke" issue creating threads in vs 2019

Question

std::mutex task_lock;
    std::mutex running_tasks_lock;
    std::vector<std::string> path;
    std::vector<std::thread *> vecOfThreads;

void __get_fileTree(std::thread *thread)
{
    qDebug() << "YES";
}

void MapSorter::get_fileTree()
{
    task_lock.lock();
    path.push_back("D:\\ymir work\\");
    task_lock.unlock();
    vecOfThreads.clear();

    for (int i = 0; i < 4; i++)
    {
        vecOfThreads.push_back(new std::thread(__get_fileTree, this));
    }

    bool tasks_done_ticker = 4;

    while (tasks_done_ticker > 0) 
    {
        Sleep(10);

        running_tasks_lock.lock();
        task_lock.lock();
        if (path.empty())
        {
            tasks_done_ticker -= 1;
        }
        else 
        {
            tasks_done_ticker = 4;
        }
        running_tasks_lock.unlock();
        task_lock.unlock();
    }

    for (std::thread *s : vecOfThreads)
    {
        s->join();
    }
}

I tryed to create 4 threads and just print a debug to test it. I get this compiler issue so i thought I may have done something wrong but after trying to change the function call several times i couldnt fix it. Any suggestions?

ERROR MESSAGES: Error messages

Changes to

vecOfThreads.push_back(new std::thread(&MapSorter::Repeatget_fileTree, this));

doesnt fix the issue

Please include the full error message in the question. It is important. — john, Nov 02 '22 at 09:12
what compiler issue? Is there an error message? Please include it in the question — 463035818_is_not_an_ai, Nov 02 '22 at 09:12
Off the top of my head I would say it should be this `std::thread(this, &MapSorter::__get_fileTree)` — john, Nov 02 '22 at 09:13
you should also post a [mcve]. The code as you posted now is expected to result in a wall of compiler errors, because eg all includes are missing — 463035818_is_not_an_ai, Nov 02 '22 at 09:13
OK, not quite right `std::thread(&MapSorter::__get_fileTree, this)` seems to be the way, see duplicate. — john, Nov 02 '22 at 09:15
But note that names containing double underscores are reserved for the compiler. You should change the name of the method. — john, Nov 02 '22 at 09:16
changed it to std::thread(&MapSorter::Repeatget_fileTree, this) but the same issue still accure — x3Syntax, Nov 02 '22 at 09:19

score 0 · Answer 1 · answered Nov 02 '22 at 09:25

I believe like this

void get_fileTree()
{
    qDebug() << "YES";
}

vecOfThreads.push_back(new std::thread(get_fileTree));

or like this

void get_fileTree(MapSorter *sorter)
{
    qDebug() << "YES";
}

vecOfThreads.push_back(new std::thread(get_fileTree, this));

Sorry about the earlier answer. When I saw this in the arguments to std::thread I assumed wrongly that get_fileTree was a member function.

score 0 · Answer 2 · answered Nov 02 '22 at 09:43

0

void MapSorter::Repeatget_fileTree()
{
    qDebug() << "YES";
}

and

vecOfThreads.push_back(new std::thread(&MapSorter::Repeatget_fileTree, this));

fixed it. Thanks.

answered Nov 02 '22 at 09:43

x3Syntax

11
2

C2672 "invoke" issue creating threads in vs 2019

2 Answers2