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5e8c5299d3
Currently, Kconfig does not complain about the recursive dependency
where 'imply' keywords are involved.
[Test Code]
config A
bool "a"
config B
bool "b"
imply A
depends on A
In the code above, Kconfig cannot calculate the symbol values correctly
due to the circular dependency. For example, allyesconfig followed by
syncconfig results in an odd behavior because CONFIG_B becomes visible
in syncconfig.
$ make allyesconfig
scripts/kconfig/conf --allyesconfig Kconfig
#
# configuration written to .config
#
$ cat .config
#
# Automatically generated file; DO NOT EDIT.
# Main menu
#
CONFIG_A=y
$ make syncconfig
scripts/kconfig/conf --syncconfig Kconfig
*
* Restart config...
*
*
* Main menu
*
a (A) [Y/n/?] y
b (B) [N/y/?] (NEW)
To detect this correctly, sym_check_expr_deps() should recurse to
not only sym->rev_dep.expr but also sym->implied.expr .
At this moment, sym_check_print_recursive() cannot distinguish
'select' and 'imply' since it does not know the precise context
where the recursive dependency has been hit. This will be solved
by the next commit.
In fact, even the document and the unit-test are confused. Using
'imply' does not solve recursive dependency since 'imply' addresses
the unmet direct dependency, which 'select' could cause.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Dirk Gouders <dirk@gouders.net>
64 lines
587 B
Plaintext
64 lines
587 B
Plaintext
# SPDX-License-Identifier: GPL-2.0
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# depends on itself
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config A
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bool "A"
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depends on A
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# select itself
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config B
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bool
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select B
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# depends on each other
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config C1
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bool "C1"
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depends on C2
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config C2
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bool "C2"
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depends on C1
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# depends on and select
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config D1
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bool "D1"
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depends on D2
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select D2
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config D2
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bool
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# depends on and imply
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config E1
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bool "E1"
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depends on E2
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imply E2
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config E2
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bool "E2"
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# property
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config F1
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bool "F1"
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default F2
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config F2
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bool "F2"
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depends on F1
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# menu
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menu "menu depending on its content"
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depends on G
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config G
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bool "G"
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endmenu
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