Re: [PATCH] Script to check for undefined Kconfig symbols - v2

[Randy Dunlap <randy.dunlap@oracle.com>]

Paolo Giarrusso wrote:
> On Fri, 24 Aug 2007 Randy Dunlap wrote:
>> On Fri, 24 Aug 2007 16:56:49 +0200 Paolo 'Blaisorblade' Giarrusso wrote:
>>
>>> In this version, I've updated the scripts to search for "\<$symb_bare\>" instead
>>> of $symb_bare in Kconfig files. Please ignore my previous message.
>>>
>>> To avoid to look manually for used but undefined Kconfig variables, I've
>>> written a script which tries do this efficiently, in case all other attention
>>> fail. It accounts for _MODULE suffix and for UML_ prefixes to Kconfig variable,
>>> but otherwise looks for exact matches (i.e. \<CONFIG_; this is done to exclude
>>> macros like MMCONFIG_).
>>>
>>> Undefined Kconfig variables should be not be removed without care, but for
>>> instance arch/i386/boot/ uses a bunch of undefined Kconfig vars:
>>>
>>> $ scripts/checkunknowndefines.sh arch/i386/boot/
>>> arch/i386/boot/video.h uses undefined symbol VIDEO_400_HACK
>>> arch/i386/boot/video-vga.c uses undefined symbol VIDEO_400_HACK
>>> arch/i386/boot/video.c uses undefined symbol VIDEO_RETAIN
>>> arch/i386/boot/video.h uses undefined symbol VIDEO_RETAIN
>>> arch/i386/boot/video.h uses undefined symbol VIDEO_SVGA
>>> arch/i386/boot/video.h uses undefined symbol VIDEO_VESA
>>> arch/i386/boot/video-vesa.c uses undefined symbol VIDEO_VESA
>>>
>>> Hope you can merge this in -mm and use it frequently (probably, a script to look for
>>> regressions in its output is useful). It should also be mentioned in
>>> SubmittingPatches if you agree.
>> or added to Documentation/SubmitChecklist.
> 
> Indeed - that's what I should have written, but I had forgot the exact file name.
> 
>> How does this script compare to
>> http://www.fsdev.net/wiki/index.php?title=Misspelled_CONFIG_variables
>> and
>> http://www.fsdev.net/wiki/index.php?title=Dead_CONFIG_variables
>> ?
> 
> They are the same, but they do not identify the files containing the dead var.
> It may be worth to just "grep back" in kernel sources for the dead symbol to
> readd this feature, but it may be slower that way.
> 
> The difference is that since I find symbols together with file name, I cannot
> use uniq but I must use that awk script.
> 
> Anyway, do we agree that a script for this should be probably
> merged in kernel sources?
> 
> Thanks for your answer.

Yes, I agree that it's useful and more convenient to be in
linux/scripts/.

-- 
~Randy
*** Remember to use Documentation/SubmitChecklist when testing your code ***