From: Bjørn Mork
...

quoted

Try following code, and you'll get a compilation error.

unsigned int can_this_fly(struct sk_buff *skb)
{
return IS_ENABLED(CONFIG_NOWAY_SIR) ? skb->unknown_field : 0;
}

Doh. Of course. Thanks for spoon feeding me that.

Of course, config_enabled(foo) could be implemented as
config_enabled_(foo, 1, 0)
Allowing you to define and test:
	IS_ENABLED_Q(CONFIG_NOWAY_SIR, skb->unknown_field, 0)

Although you'd probably need to paste the expansions of both 'foo'
'foo_MODULE' onto __ARG_PLACEHOLDER_ to avoid the ||.

More useful might be IF_ENABLED(foo, x) which expands to either
x or nothing at all.
The you could conditionally generate the chunks of format statement
as well as the parameter list.

OTOH you might want readable code!

	David