exceptioncollision.cpp

// This program exposes a bug. Use alpine Linux and compile as follows:
//    g++ exceptioncollision.cpp -o exceptioncollision -O0 -Wall -std=c++14 -lpthread -static
// Then execute the static executable multiple times:
//    while true ; do ./exceptioncollision ; date ; done
// after a few tries it will freeze.

#include <thread>
#include <atomic>
#include <chrono>

std::atomic<int> letsgo{0};

void waiter() {
  size_t count = 0;
  while (letsgo == 0) {
    ++count;
  }
  try {
    throw 42;
  } catch (int const& s) {
  }
}

int main(int, char*[]) {
#ifdef REPAIR
  try { throw 42; } catch (int const& i) {}
#endif
  std::thread t1(waiter);
  std::thread t2(waiter);
  std::this_thread::sleep_for(std::chrono::milliseconds(10));
  letsgo = 1;
  t1.join();
  t2.join();
  return 0;
}