1 // RUN: %clangxx_tsan -O1 %s -o %t && %deflake %run %t 2>&1 | FileCheck %s
2 #include "test.h"
3
4 long long Data;
5 long long Sync;
6
Thread1(void * x)7 void *Thread1(void *x) {
8 Data++;
9 __atomic_store_n(&Sync, 1, __ATOMIC_RELEASE);
10 barrier_wait(&barrier);
11 barrier_wait(&barrier);
12 return NULL;
13 }
14
Thread2(void * x)15 void *Thread2(void *x) {
16 barrier_wait(&barrier);
17 if (__atomic_load_n(&Sync, __ATOMIC_RELAXED) != 1)
18 exit(0);
19 // This store must terminate release sequence of the store in Thread1,
20 // thus tsan must detect race between Thread1 and main on Data.
21 __atomic_store_n(&Sync, 2, __ATOMIC_RELEASE);
22 barrier_wait(&barrier);
23 return NULL;
24 }
25
main()26 int main() {
27 barrier_init(&barrier, 3);
28 pthread_t t[2];
29 pthread_create(&t[0], NULL, Thread1, NULL);
30 pthread_create(&t[1], NULL, Thread2, NULL);
31 barrier_wait(&barrier);
32 barrier_wait(&barrier);
33 if (__atomic_load_n(&Sync, __ATOMIC_ACQUIRE) != 2)
34 exit(0);
35 if (Data != 1)
36 exit(0);
37 pthread_join(t[0], NULL);
38 pthread_join(t[1], NULL);
39 fprintf(stderr, "DONE\n");
40 return 0;
41 }
42
43 // CHECK: WARNING: ThreadSanitizer: data race
44 // CHECK: Read
45 // CHECK: #0 main
46 // CHECK: Previous write
47 // CHECK: #0 Thread1
48 // CHECK: Location is global 'Data'
49 // CHECK: DONE
50