Re: [PATCH 5/5] kconfig: limit IS_ENABLED & similar to CPP usage

[Paul Gortmaker <paul.gortmaker@windriver.com>]

On 12-04-11 08:04 PM, Linus Torvalds wrote:
> On Wed, Apr 11, 2012 at 4:50 PM, Paul Gortmaker
> <paul.gortmaker@windriver.com> wrote:
>> Using IS_ENABLED() within C (vs. within CPP #if statements) requires
>> us to actually define every possible bool/tristate Kconfig option
>> twice (__enabled_* and __enabled_*_MODULE variants).
> 
> Why do you keep the __enabled_*[_MODULE] things alive at all?

Good point.  Clearly I wasn't aggressive enough in my shitectomy.
Testing with no __enabled_* stuff now.  That reduces the line
count even more, which is nice.

I've not auto-prefixed the CONFIG_ though, since that seems to break
the grep use case.

P.

> 
> Why can't you just check the CONFIG_xyz[_MODULE] #defines directly?
> 
> IOW, why isn't IS_ENABLED() just
> 
>   #define IS_ENABLED(option) \
>     (defined(CONFIG_##option) || defined(CONFIG_##option##_MODULE))
> 
>   #define IS_BUILTIN(option) \
>     (defined(CONFIG_##option))
> 
> and we're done with it all? What's the advantage of the __enabled_
> thing again, when you depend on the preprocessor anyway?
> 
>                       Linus