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

-- 
Catalin