| 1 | // RUN: %clangxx_tsan -O1 %s -o %t && %deflake %run %t | FileCheck %s |
| 2 | #include <pthread.h> |
| 3 | #include <stdlib.h> |
| 4 | #include <stdio.h> |
| 5 | #include <sched.h> |
| 6 | |
| 7 | struct Cache { |
| 8 | int x; |
| 9 | }; |
| 10 | |
| 11 | Cache g_cache; |
| 12 | |
| 13 | Cache *CreateCache() { |
| 14 | g_cache.x = rand(); |
| 15 | return &g_cache; |
| 16 | } |
| 17 | |
| 18 | _Atomic(Cache*) queue; |
| 19 | |
| 20 | void *Thread1(void *x) { |
| 21 | static Cache *c = CreateCache(); |
| 22 | __c11_atomic_store(&queue, c, 0); |
| 23 | return 0; |
| 24 | } |
| 25 | |
| 26 | void *Thread2(void *x) { |
| 27 | Cache *c = 0; |
| 28 | for (;;) { |
| 29 | c = __c11_atomic_load(&queue, 0); |
| 30 | if (c) |
| 31 | break; |
| 32 | sched_yield(); |
| 33 | } |
| 34 | if (c->x >= RAND_MAX) |
| 35 | exit(status: 1); |
| 36 | return 0; |
| 37 | } |
| 38 | |
| 39 | int main() { |
| 40 | pthread_t t[2]; |
| 41 | pthread_create(newthread: &t[0], attr: 0, start_routine: Thread1, arg: 0); |
| 42 | pthread_create(newthread: &t[1], attr: 0, start_routine: Thread2, arg: 0); |
| 43 | pthread_join(th: t[0], thread_return: 0); |
| 44 | pthread_join(th: t[1], thread_return: 0); |
| 45 | } |
| 46 | |
| 47 | // CHECK: WARNING: ThreadSanitizer: data race |
| 48 | |