Re: Where's the documentation for Kconfig?

[Roman Zippel <zippel@linux-m68k.org>]

Hi,

On Sat, 2 Nov 2002, Erik Andersen wrote:

> On Thu Oct 31, 2002 at 03:43:26PM +0100, Roman Zippel wrote:
> > kconfig:
> > config /symbol/
> > 	bool /prompt/
> > 	default /word/
> 
> Suppose at some time we wished to move things like architecture
> specific CFLAGS into Kconfig.  It would be implemented as a
> "string" object and would look something like:
> 
> config CPU_CFLAGS
>         string
>         default "-march=i386" if M386
>         default "-march=i486" if M486
>         default "-march=i586" if M586
>         default "-march=i686 -malign-functions=4" if MK7

It's possible, but I don't think we will start in the arch part. More 
interesting would be driver entries like:

driver foo
	tristate "foo support"
	depends on BAR
	source foo.c

part of this could also be:

	cflags "..." [if ...]


> So for the K7 case, we could expand it to something much more
> sneaky later on, something like:
>     default "$(call check_gcc,-march=athlon,-march=i686 -malign-functions=4)" if MK7
> and the check_gcc macro could be correctly evaluated by make.
> Neat stuff.  (Such a check_gcc macro does not yet exist in the 
> kernel Makefiles, but surely will sometime).

Having make specific macros in the configuration is not really a good 
idea. Such tests should rather be done by a shell script and its output 
would be imported into the build system.

bye, Roman