compiler-rt/test/tsan/fork_multithreaded3.cpp

   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
  10 static void *racer(void *p) {
  11   *(int*)p = 42;
  12   return 0;
  13 }
  14
  15 int 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