Quoting Adrian Bunk <bunk@fs.tum.de>:
> > Anything you put in BUG_ON() must *NOT* have side effects.
> >...
> 
> I'd have said exactly the same some time ago, but I was convinced by 
> Arjan that if done correctly, a BUG_ON() with side effects is possible  
> with no extra cost even if you want to make BUG configurably do nothing.

#if is_debugging_on
# define BUG_ON(x) do { if (unlikely(x)) BUG(); } while (0)
#else
# define BUG_ON(x) do { if (x) { /* nothing */ } } while (0)
#endif

> cu
> Adrian
> 

-- 
Regards Michael Buesch  [ http://www.tuxsoft.de.vu ]