CLANG TSAN different result on multiple run same program

Question

I have tried example from CLANG TSAN documentation (https://clang.llvm.org/docs/ThreadSanitizer.html):

#include <pthread.h>
int Global;
void *Thread1(void *x) {
  Global = 42;
  return x;
}
int main() {
  pthread_t t;
  pthread_create(&t, NULL, Thread1, NULL);
  Global = 43;
  pthread_join(t, NULL);
  return Global;
}

When I compile and run this example, the result is not uniform. I have to run the program several times (multiple program run), to get correct result. Is it normal behavior?