How to crash a thread with a shared_ptr reference

thread.cc

#include <memory>
#include <iostream>
#include <thread>


int main()
{
    std::shared_ptr<std::thread> mythread;

    mythread.reset(
        new std::thread(
            [&]() {
                std::cout << "Thread here!" << std::endl;
#ifdef DO_CRASH
                mythread.reset();
#endif
            }
        )
    );

    std::cout << "Main function" << std::endl;
#ifndef DO_CRASH
    mythread->join();
    mythread.reset();
#endif
    
    return 0;
}