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| // RUN: %clang_tsan -O1 %s -o %t && %deflake %run %t | FileCheck %s
| #include "test.h"
|
| // We want to establish the following sequence of accesses to X:
| // - main thread writes X
| // - thread2 reads X, this read happens-before the write in main thread
| // - thread1 reads X, this read is concurrent with the write in main thread
| // Write in main thread and read in thread1 should be detected as a race.
| // Previously tsan replaced write by main thread with read by thread1,
| // as the result the race was not detected.
|
| volatile long X, Y, Z;
|
| void *Thread1(void *x) {
| barrier_wait(&barrier);
| barrier_wait(&barrier);
| Y = X;
| return NULL;
| }
|
| void *Thread2(void *x) {
| Z = X;
| barrier_wait(&barrier);
| return NULL;
| }
|
| int main() {
| barrier_init(&barrier, 2);
| pthread_t t[2];
| pthread_create(&t[0], 0, Thread1, 0);
| X = 42;
| barrier_wait(&barrier);
| pthread_create(&t[1], 0, Thread2, 0);
| pthread_join(t[0], 0);
| pthread_join(t[1], 0);
| return 0;
| }
|
| // CHECK: WARNING: ThreadSanitizer: data race
|
|
