#include <thread>
#include <vector>
#include <unordered_map>

class MyClass
{
    public:
        MyClass(){
            printf("%p\n", this);
        }
        ~MyClass(){
            printf("~%p\n", this);
        }

        std::unordered_map<int, int> member;
};

thread_local MyClass threadLocalObject;

int main(){
    std::vector<std::thread> threads;

    for (int i = 0; i < 40; ++i){
        threads.emplace_back([](){
            printf("%ld\n", threadLocalObject.member.size());
        });
    }

    for (auto &thread : threads)
        thread.join();

    return 0;
}