What question was that? Folding back across that distance is not possible
in a Git workflow. I do regular cross-builds - the build bug did not trigger
with the ia64 defconfig.

I'm confused by this, as it definitely triggered for me.  Perhaps
my build scripts do things a bit differently.  Essentially I do:

        $ for c in `ls arch/ia64/configs`
        > do
        >       cp arch/ia64/configs/$i .config
        >       yes '' | make oldconfig
        >       make
        > done

Which takes the default answer for any new questions that crop
up.  This enabled the GRU driver in the case of the generic_defconfig,
and so the build failed because of the lack of asm/uv.h

-Tony