forked from Minki/linux
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>
34 lines
1.0 KiB
Plaintext
34 lines
1.0 KiB
Plaintext
# Select broken dependency issue
|
|
# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
#
|
|
# Test with:
|
|
#
|
|
# make KBUILD_KCONFIG=Documentation/kbuild/Kconfig.select-break menuconfig
|
|
#
|
|
# kconfig will not complain and enable this layout for configuration. This is
|
|
# currently a feature of kconfig, given select was designed to be heavy handed.
|
|
# Kconfig currently does not check the list of symbols listed on a symbol's
|
|
# "select" list, this is done on purpose to help load a set of known required
|
|
# symbols. Because of this use of select should be used with caution. An
|
|
# example of this issue is below.
|
|
#
|
|
# The option B and C are clearly contradicting with respect to A.
|
|
# However, when A is set, C can be set as well because Kconfig does not
|
|
# visit the dependencies of the select target (in this case B). And since
|
|
# Kconfig does not visit the dependencies, it breaks the dependencies of B
|
|
# (!A).
|
|
|
|
mainmenu "Simple example to demo kconfig select broken dependency issue"
|
|
|
|
config A
|
|
bool "CONFIG A"
|
|
|
|
config B
|
|
bool "CONFIG B"
|
|
depends on !A
|
|
|
|
config C
|
|
bool "CONFIG C"
|
|
depends on A
|
|
select B
|