Re: [PATCH] BUILD_BUG_ON() should not use array type

[Alexey Dobriyan]

> > +/* Force a compilation error if condition is constant and true */
> > +#define MAYBE_BUILD_BUG_ON(cond) ((void)sizeof(char[1 - 2 * !!(cond)]))
> 
> MAYBE_BUILD_BUG_ON() hurts my brain.  It's doing:
> 
> 	if (__builtin_constant_p(expr))
> 		BUILD_BUG_ON(expr);
> 
> yes?  For inlined (or macro) callsites which can be used with constant
> or non-constant args.
> 
> It's tempting to just zap the one callsite and not add this at all,

Yes, please. There should be no maybes in kernel.

Imagine probabilistic BUG_ON(). Imagine probabilistic refcounting: maybe_get_net().

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/