text: #include <pthread.h>
  #include <stdio.h>
  
  int myglobal;
  pthread_mutex_t mutex1 = PTHREAD_MUTEX_INITIALIZER;
  pthread_mutex_t mutex2 = PTHREAD_MUTEX_INITIALIZER;
  
  void *t_fun(void *arg) {
    int *p = &myglobal;
    pthread_mutex_lock(&mutex1);
    *p = *p + 1; // NOWARN!
    pthread_mutex_unlock(&mutex1);
    return NULL;
  }
  
  int main(void) {
    pthread_t id;
    pthread_create(&id, NULL, t_fun, NULL);
    pthread_mutex_lock(&mutex1);
    myglobal=myglobal+1; // NOWARN!
    pthread_mutex_unlock(&mutex1);
    pthread_join (id, NULL);
    return 0;
  }
  