text: // RUN: %clangxx_tsan -O1 %s -o %t && not %t 2>&1 | FileCheck %s
  #include <pthread.h>
  #include <unistd.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <stddef.h>
  
  static int malloc_count;
  static int free_count;
  
  extern "C" {
  void __tsan_malloc_hook(void *ptr, size_t size) {
    (void)ptr;
    (void)size;
    __sync_fetch_and_add(&malloc_count, 1);
  }
  
  void __tsan_free_hook(void *ptr) {
    (void)ptr;
    __sync_fetch_and_add(&free_count, 1);
  }
  }
  
  void *Thread1(void *x) {
    ((int*)x)[0]++;
    return 0;
  }
  
  void *Thread2(void *x) {
    sleep(1);
    ((int*)x)[0]++;
    return 0;
  }
  
  int main() {
    int *x = new int;
    pthread_t t[2];
    pthread_create(&t[0], 0, Thread1, x);
    pthread_create(&t[1], 0, Thread2, x);
    pthread_join(t[0], 0);
    pthread_join(t[1], 0);
    delete x;
    if (malloc_count == 0 || free_count == 0) {
      fprintf(stderr, "FAILED %d %d\n", malloc_count, free_count);
      exit(1);
    }
    fprintf(stderr, "DONE\n");
  }
  
  // CHECK: WARNING: ThreadSanitizer: data race
  // CHECK-NOT: FAILED
  // CHECK: DONE
  