1 // RUN: %clangxx_tsan -O1 %s -o %t && %run %t 2>&1 | FileCheck %s
2 #include <pthread.h>
3 #include <stdio.h>
4 #include <unistd.h>
5 
6 int fds[2];
7 int X;
8 
Thread1(void * x)9 void *Thread1(void *x) {
10   X = 42;
11   write(fds[1], "a", 1);
12   return NULL;
13 }
14 
Thread2(void * x)15 void *Thread2(void *x) {
16   char buf;
17   while (read(fds[0], &buf, 1) != 1) {
18   }
19   X = 43;
20   return NULL;
21 }
22 
main()23 int main() {
24   pipe(fds);
25   pthread_t t[2];
26   pthread_create(&t[0], NULL, Thread1, NULL);
27   pthread_create(&t[1], NULL, Thread2, NULL);
28   pthread_join(t[0], NULL);
29   pthread_join(t[1], NULL);
30   fprintf(stderr, "OK\n");
31 }
32 
33 // CHECK-NOT: WARNING: ThreadSanitizer: data race
34