1// RUN: %clangxx_tsan -O1 %s -o %t && %run %t 2>&1 | FileCheck %s
2#include <stdlib.h>
3#include <stdio.h>
4#include <errno.h>
5#include <pthread.h>
6#include <unistd.h>
7#include <sys/types.h>
8#include <sys/wait.h>
9
10static void *racer(void *p) {
11  *(int*)p = 42;
12  return 0;
13}
14
15int main() {
16  switch (fork()) {
17  default:  // parent
18    while (wait(0) < 0) {}
19    break;
20  case 0:  // child
21    {
22      int x = 0;
23      pthread_t th1, th2;
24      pthread_create(&th1, 0, racer, &x);
25      pthread_create(&th2, 0, racer, &x);
26      pthread_join(th1, 0);
27      pthread_join(th2, 0);
28      exit(0);
29      break;
30    }
31  case -1:  // error
32    fprintf(stderr, "failed to fork (%d)\n", errno);
33    exit(1);
34  }
35  fprintf(stderr, "OK\n");
36}
37
38// CHECK: ThreadSanitizer: data race
39// CHECK: OK
40
41