1 # Simple Kconfig recursive issue
2 # ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3 #
4 # Test with:
5 #
6 # make KBUILD_KCONFIG=Documentation/kbuild/Kco
7 #
8 # This Kconfig file has a simple recursive dep
9 # understand why this recursive dependency iss
10 # Kconfig needs to address. We iterate over wh
11 # by stepping through the questions it needs t
12 #
13 # * What values are possible for CORE?
14 #
15 # CORE_BELL_A_ADVANCED selects CORE, which mea
16 # that are possible for CORE. So for example i
17 # CORE must be 'y' too.
18 #
19 # * What influences CORE_BELL_A_ADVANCED?
20 #
21 # As the name implies CORE_BELL_A_ADVANCED is
22 # CORE_BELL_A so naturally it depends on CORE_
23 # we know CORE_BELL_A_ADVANCED can be 'y' too.
24 #
25 # * What influences CORE_BELL_A?
26 #
27 # CORE_BELL_A depends on CORE, so CORE influen
28 #
29 # But that is a problem, because this means th
30 # what values are possible for CORE we ended u
31 # regarding possible values of CORE itself aga
32 # question of what are the possible values of
33 # tools run in a loop. When this happens Kconf
34 # the "recursive dependency detected" error.
35 #
36 # Reading the Documentation/kbuild/Kconfig.rec
37 # obvious that an easy solution to this proble
38 # of the "select CORE" from CORE_BELL_A_ADVANC
39 # since CORE_BELL_A depends on CORE. Recursive
40 # so trivial to resolve, we provide another ex
41 # implications of this recursive issue where t
42 # easy to understand. Note that matching seman
43 # CORE also consist of a solution to this recu
44
45 mainmenu "Simple example to demo kconfig recur
46
47 config CORE
48 tristate
49
50 config CORE_BELL_A
51 tristate
52 depends on CORE
53
54 config CORE_BELL_A_ADVANCED
55 tristate
56 depends on CORE_BELL_A
57 select CORE
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