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From: David Brownell <david-b@pacbell.net>
To: Randy Dunlap <randy.dunlap@oracle.com>
Subject: Re: [BUILD FAILURE 11/12] Next April 21 : PPC64 randconfig
	[drivers/usb/host/ohci-hcd.o]
Date: Tue, 21 Apr 2009 19:19:37 -0700
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On Tuesday 21 April 2009, Randy Dunlap wrote:
> 
> > Since its feasible to say 'n' to both we get the compile error.  How do
> > we enforce having at least one set?
> 
> Looks like using "choice" without "optional" would do it.
> See Documentation/kbuild/kconfig-language.txt and various examples
> in Kconfig* files.

That won't quite work ... "at least one" includes "two"
(i.e. a PCI card in little-endian, a native controller
in big-endian).  Real-world systems need such configs,
or so I'm told, and that's why their supported.

Is there maybe a way to force Kconfig to just reject
such illegal configs -- neither option set -- rather
than trying some how to fix it?

Or maybe ... if neither one is set, have the header
force both on, and issue a warning.