Re: [PATCH v2] kconfig: autogenerated config_is_xxx macro

[Michal Marek]

On 7.5.2011 03:50, Jean-Christophe PLAGNIOL-VILLARD wrote:
> On 12:19 Fri 06 May     , Arnaud Lacombe wrote:
> > Why would it be a good thing ?
> >
> > Most configuration-dependent code inside functions tends to be moved
> > to a static inline already, which get conditionally defined based on
> > the CONFIG_<foo>. If it is not, then the code is badly architectured
> > (->  bad). Using that if(xxx) notation would also lead to yet more
> > heavily indented function (->  bad). Moreover, this introduces
> > yet-another way to check for an information (->  bad), and you will end
> > up with mixing the config_is_<xxx>  notation inside a function
> > declaration, and CONFIG_<xxx>  when not inside a function (->  bad)
> >
> > Actually, this is even worse than that as you'll not be able to hide
> > structure (or structure members) inside CONFIG_<xxx>  and use that
> > structure (or structure members) in config_is_<xxx>  protected block
> > without causing compile-time failure.
> sorry but conditionnal structure members is bad practice
> you save nearly no space nut for the test of the code in multiple
> configuration. Use union for this.
>
> the compile-time failure is good here. it's means your code is not generic.
>
> specially when you want to keep code running on multiple soc/arch keep compiling
> no matter the configuration
>
> #ifdef in the code is a really bad habit

Do you have proof of concept patches that make use of the config_is_xxx 
macros? Acked by the respective subsystem maintainers? It would be a 
good idea to send them along to show that this feature is going to be 
actually used.

Michal
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