std::thread stopped after 1 hour

Function waitSignal stopped work after 55-80 min after starting program.

void waitSignal()
{
  while(true){
    // code to wait some signal
  }
}


int main()
{
  std::thread thr1(waitSignal);
  thr1.detach();
}

But main function continue work. What to do it thread work without stopping?