[RFC PATCH] Kconfig: Enable Kconfig fragments to be used for defconfig

[Grant Likely]

On Fri, Jul 16, 2010 at 12:19 PM, Nicolas Pitre <nico at fluxnic.net> wrote:
> On Fri, 16 Jul 2010, Grant Likely wrote:
>
>> On Fri, Jul 16, 2010 at 10:03 AM, Catalin Marinas
>> <catalin.marinas at arm.com> wrote:
>> > On Wed, 2010-07-14 at 00:04 +0100, Grant Likely wrote:
>> >> - It still doesn't resolve dependencies.  A solver would help with this.
>> >>   For the time being I work around the problem by running the generated
>> >>   config through 'oldconfig' and looking for differences.  If the files
>> >>   differ (ignoring comments and generateconfig_* options) after oldconfig,
>> >>   then the <board>_defconfig target returns a failure.  (but leaves the
>> >>   new .config intact so the user can resolve it with menuconfig).  This
>> >>   way at least the user is told when a Kconfig fragment is invalid.
>> >
>> > It's not a solver but I'm pushing a patch to warn on selecting symbols
>> > with unmet dependencies so that you can select further symbols (manual
>> > solving). The patch is in linux-next but you also can grab it from:
>> >
>> > http://git.kernel.org/?p=linux/kernel/git/cmarinas/linux-2.6-cm.git;a=commitdiff_plain;h=5d87db2d2a332784bbf2b1ec3e141486f4d41d6f
>>
>> sfr and I were talking about your patch the other day.  Just warning
>> on incomplete dependencies is enough to make it actually workable for
>> me (without my ugly post-processing step).  I was very happy to hear
>> that it is in linux-next.
>>
>> Last missing piece is being able to do "select FOO = n", which Stephen
>> is currently working on.
>
> Instead of (or in addition to) warning for incomplete
> dependencies, I'd much prefer if the prerequisites were recursively
> selected automatically.  This way if some options are moved inside a
> submenu at some point with a config symbol for that subcategory
> (e.g. CONFIG_NETDEV_1000), or if the subsystem is reorganized into
> submodules that are required for some driver to work, then my
> config will still be fine.
>
> For example, if I want CONFIG_MTD_CMDLINE_PARTS=y, the system may be
> smart enough to notice and automatically enable CONFIG_MTD and
> CONFIG_MTD_PARTITIONS without having to carry those in the defconfig.

I fully agree.  However, the warnings make the system work now while
we wait for a full solver to be implemented.

g.