yes, it's a kconfig bug: Kconfig must either not allow complex selects
(during its initial parsing pass of the Kconfig dependnecy tree) or
handle the dependencies correctly.
The current "allow them silently and pepper the kernel with build
errors" approach is obviously silly.
We already have over 100 bugfixes in the tree from the past 3 years due
to kconfig's inability to figure out the correct dependencies. (count:
rising steadily)
Changes to the Kconfig tool to address this design bug did not get
picked up. See for example this quick patch from Vegard half a year ago:
http://lkml.org/lkml/2008/5/4/13
that patch was not adopted and the config options in the warning log
were later on frequent participants in build failures and subsequent
stream of trivial fixes.
Ingo
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