/* Stripped-down API equivalent */
typedef struct object object;

typedef int errcode;

extern errcode SetUserContext(object* obj, void* user_context);
extern errcode GetUserContext(object* obj, void** user_context);


/* API-using code */

typedef struct my_user_context my_user_context;

extern my_user_context* AllocMyUserContext(void);

void my_set_func(object* the_object)
{
  my_user_context* uc;
  errcode err;

  uc = AllocMyUserContext();

  err = SetUserContext(the_object, (void*)uc);
}

void my_get_func(object* the_object)
{
  my_user_context* uc;
  errcode err;

  /* Breaks strict aliasing rules? */
  err = GetUserContext(the_object, (void**)&uc);
}


void my_get_func2(object* the_object)
{
  my_user_context* uc;
  void* uc_v;
  errcode err;

  err = GetUserContext(the_object, &uc_v);
  uc = uc_v;
}