#include <liblockdep/rwlock.h>
  
  void main(void)
  {
  	pthread_rwlock_t a, b;
  
  	pthread_rwlock_init(&a, NULL);
  	pthread_rwlock_init(&b, NULL);
  
  	pthread_rwlock_wrlock(&a);
  	pthread_rwlock_rdlock(&b);
  	pthread_rwlock_wrlock(&a);
  }