Re: [PATCH] kbuild: document recursive dependency limitation / resolution

From: Luis R. Rodriguez
Date: Wed Sep 23 2015 - 11:48:16 EST


On Wed, Jul 29, 2015 at 01:34:50PM -0700, Randy Dunlap wrote:
> On 07/29/15 13:09, Luis R. Rodriguez wrote:
> > +
> > +Kconfig recursive dependency limitations
> > +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > +
> > +If you've hit the Kconfig error: "recursive dependency detected" you've run
> > +into a recursive dependency issue with Kconfig. Kconfig does not do recursive
> > +dependency resolution, this has a few implications for Kconfig file writers. In
>
> maybe s/,/;/

Fixed.

> > +practice it means that for instance if a driver A selects a few kconfig symbols
> > +another driver B which selects any of these symbols cannot negate any of the
> > +symbols the driver A selected. Because of this current limitation developers
> > +who run into this type of recursive dependency issue have two diverging
> > +options:
> > +
> > + a) Either swap all "select FOO" to "depends on FOO" or,
> > + b) Change the offending "depends on FOO" to "select FOO"
> > +
> > +Kconfig's limitations can be addressed by implementing a SAT solver for it,
> > +but until then, Kconfig is limitted to require developers to use one of
>
> limited
>

I've re-written this section, thanks for the review.

Luis
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