docs: note about select in kconfig-language.txt

A warning note from Sam Ravnborg about kconfig's select evilness,
dependencies and the future (slightly corrected).

Signed-off-by: Jarek Poplawski <jarkao2@o2.pl>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Jarek Poplawski 2007-08-10 13:01:04 -07:00 committed by Linus Torvalds
parent 09736bd36a
commit f8a745942b

View file

@ -98,6 +98,15 @@ applicable everywhere (see syntax).
times, the limit is set to the largest selection.
Reverse dependencies can only be used with boolean or tristate
symbols.
Note:
select is evil.... select will by brute force set a symbol
equal to 'y' without visiting the dependencies. So 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 promts 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.
- numerical ranges: "range" <symbol> <symbol> ["if" <expr>]
This allows to limit the range of possible input values for int