llvm-project/compiler-rt/test/tsan/write_in_reader_lock.cc

36 lines
912 B
C++

// RUN: %clangxx_tsan -O1 %s -o %t && %deflake %run %t | FileCheck %s
#include <pthread.h>
#include <unistd.h>
pthread_rwlock_t rwlock;
int GLOB;
void *Thread1(void *p) {
(void)p;
pthread_rwlock_rdlock(&rwlock);
// Write under reader lock.
sleep(1);
GLOB++;
pthread_rwlock_unlock(&rwlock);
return 0;
}
int main(int argc, char *argv[]) {
pthread_rwlock_init(&rwlock, NULL);
pthread_rwlock_rdlock(&rwlock);
pthread_t t;
pthread_create(&t, 0, Thread1, 0);
volatile int x = GLOB;
(void)x;
pthread_rwlock_unlock(&rwlock);
pthread_join(t, 0);
pthread_rwlock_destroy(&rwlock);
return 0;
}
// CHECK: WARNING: ThreadSanitizer: data race
// CHECK: Write of size 4 at {{.*}} by thread T1{{.*}}:
// CHECK: #0 Thread1(void*) {{.*}}write_in_reader_lock.cc:13
// CHECK: Previous read of size 4 at {{.*}} by main thread{{.*}}:
// CHECK: #0 main {{.*}}write_in_reader_lock.cc:23