2.6 bug: kconfig implementation doesn't match the spec

From: Adrian Bunk <bunk@fs.tum.de>
To: Roman Zippel <zippel@linux-m68k.org>
Cc: linux-kernel@vger.kernel.org
Subject: 2.6 bug: kconfig implementation doesn't match the spec
Date: Fri, 8 Aug 2003 16:51:08 +0200	[thread overview]
Message-ID: <20030808145107.GY16091@fs.tum.de> (raw)

Hi Roman,

the implementation of the !-operator doesn't match the spec in
Documentation/kbuild/kconfig-language.txt

kconfig-language.txt says:

<--  snip  -->

...
           '!' <expr>                           (5)
...
(5) Returns the result of (2-/expr/).
...
An expression can have a value of 'n', 'm' or 'y' (or 0, 1, 2
respectively for calculations). A menu entry becomes visible when it's
expression evaluates to 'm' or 'y'.
...

<--  snip  -->

The current implementation evaluates !m to 0 instead of 1.

An example:

config FOO
        tristate
        default m

config BAR
        tristate
        default y if !FOO
        default n

According to the kconfig spec BAR should be y, but the implementation in
2.6.0-mm5 sets BAR to n.

BTW:
The semantics of the implemention seems to be a bit less surprising 
than the semantics of the spec.

cu
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed