Kernel Bug Tracker – Bug 22112
A couple of Kconfig warnings
Last modified: 2010-11-18 23:08:15 UTC
Subject : A couple of Kconfig warnings
Submitter : Fabio Comolli <firstname.lastname@example.org>
Date : 2010-10-30 11:48
Message-ID : AANLkTik41vfVn6K0UDYfoCK7O8j2UHsqhGNdbVckt-PA@mail.gmail.com
References : http://marc.info/?l=linux-kernel&m=128843932821411&w=2
This entry is being used for tracking a regression from 2.6.36. Please don't
close it until the problem is fixed in the mainline.
This is not a regression. For years, Documentation/kbuild/kconfig-language.txt had the following comment about the usage of the "select" directive:
select should be used with care. select will force
a symbol to a value without visiting the dependencies.
By abusing select you are able to select a symbol FOO even
if FOO depends on BAR that is not set.
In general use select only for non-visible symbols
(no prompts anywhere) and for symbols with no dependencies.
That will limit the usefulness but on the other hand avoid
the illegal configurations all over.
kconfig should one day warn about such things.
Until 2.6.36, kconfig was not warning (well, it was, but was silenced due to a late bugfix) about these abusive usage. Now it is.