1c199f2878
Recursive dependency issues with kconfig are unavoidable due to some limitations with kconfig, since these issues are recurring provide a hint to the user how they can resolve these dependency issues and also document why such limitation exists. While at it also document a bit of future prospects of ways to enhance Kconfig, including providing formal semantics and evaluation of use of a SAT solver. If you're interested in this work or prospects of it check out the kconfig-sat project wiki [0] and mailing list [1]. [0] http://kernelnewbies.org/KernelProjects/kconfig-sat [1] https://groups.google.com/d/forum/kconfig-sat Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: James Bottomley <jbottomley@odin.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Paul Bolle <pebolle@tiscali.nl> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Takashi Iwai <tiwai@suse.de> Cc: "Yann E. MORIN" <yann.morin.1998@free.fr> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Mate Soos <soos.mate@gmail.com> Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com> Signed-off-by: Michal Marek <mmarek@suse.com>
33 lines
1 KiB
Text
33 lines
1 KiB
Text
# Select broken dependency issue
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# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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#
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# Test with:
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#
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# make KBUILD_KCONFIG=Documentation/kbuild/Kconfig.select-break menuconfig
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#
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# kconfig will not complain and enable this layout for configuration. This is
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# currently a feature of kconfig, given select was designed to be heavy handed.
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# Kconfig currently does not check the list of symbols listed on a symbol's
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# "select" list, this is done on purpose to help load a set of known required
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# symbols. Because of this use of select should be used with caution. An
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# example of this issue is below.
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#
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# The option B and C are clearly contradicting with respect to A.
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# However, when A is set, C can be set as well because Kconfig does not
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# visit the dependencies of the select target (in this case B). And since
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# Kconfig does not visit the dependencies, it breaks the dependencies of B
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# (!A).
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mainmenu "Simple example to demo kconfig select broken dependency issue"
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config A
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bool "CONFIG A"
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config B
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bool "CONFIG B"
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depends on !A
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config C
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bool "CONFIG C"
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depends on A
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select B
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