test/tsan/libdispatch/groups-destructor.cpp

// RUN: %clangxx_tsan %s %link_libcxx_tsan -o %t
// RUN: %run %t 2>&1 | FileCheck %s --implicit-check-not='ThreadSanitizer'

#include <dispatch/dispatch.h>

#include <atomic>
#include <cstdio>
#include <memory>

std::atomic<long> destructor_counter(0);

struct MyStruct {
  virtual ~MyStruct() {
    usleep(10000);
    std::atomic_fetch_add_explicit(&destructor_counter, 1, std::memory_order_relaxed);
  }
};

int main(int argc, const char *argv[]) {
  std::fprintf(stderr, "Hello world.\n");

  dispatch_queue_t q = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
  dispatch_group_t g = dispatch_group_create();

  for (int i = 0; i < 100; i++) {
    std::shared_ptr<MyStruct> shared(new MyStruct());

    dispatch_group_async(g, q, ^{
      shared.get(); // just to make sure the object is captured by the block
    });
  }

  dispatch_group_wait(g, DISPATCH_TIME_FOREVER);

  if (destructor_counter != 100) {
    std::abort();
  }

  std::fprintf(stderr, "Done.\n");
}

// CHECK: Hello world.
// CHECK: Done.