Re: [RFC PATCH] media: consolidation of -I flags

T Dent
2010-10-05T22:27:40Z

On 10/5/10, Sam Ravnborg <sam@ravnborg.org> wrote:
> On Sun, Sep 26, 2010 at 02:00:47PM -0700, matt mooney wrote:
>> I have been doing cleanup of makefiles, namely replacing the older style
>> compilation flag variables with the newer style. While doing this, I
>> noticed that the majority of drivers in the media subsystem seem to rely
>> on a few core header files:
>>
>> -Idrivers/media/video
>> -Idrivers/media/common/tuners
>> -Idrivers/media/dvb/dvb-core
>> -Idrivers/media/dvb/frontends
>>
>> This patch removes them from the individual makefiles and puts them in
>> the main makefile under media.
> Using subdir-ccflags-y has one drawback you need to be aware of.
> The variable is _not_ picked up if you build individual drivers like
> this:
>
>
> make drivers/media/dvb/b2c2/
>
> So with this patch applied it is no longer possible to do so.
> It is better to accept the duplication rather than breaking
> the build of individual drivers.
>
>>
>> If neither idea is considered beneficial, I will go ahead and replace
>> the older variables with the newer ones as is.
>
> This is the right approach.
>
> You could consider to do a more general cleanup:
> 1) replace EXTRA_CFLAGS with ccflags-y (the one you suggest)
> 2) replace use of <module>-objs with <module>-y
> 3) break continued lines into several assignments

I have a question when you say this do you mean change something like this:

r8187se-objs :
to

r8187se-y :
If so, I could start working on that in the staging directory.

> People very often uses '\' to break long lines, where a
> simple += would be much more readable.
> But this topic may be personal - I never uses "\" in my .c code unless in
> macros,
> and I have applied the same rule for Makefiles.
> An ugly example is drivers/media/Makefile
> 4) In general use ":=" instead of "=".
> Add using "+=" as first assignment is OK - but it just looks plain wrong
> 5) some files has a mixture of spaces/tabs (are red in my vim)
> dvb-core/Makefile is one such example
> 6) remove useless stuff
> siano/Makefile has some strange assignments to EXTRA_CFLAGS
> 7) Likely a few more items to look after...
>
> This is more work - but then you finish a Makefile rather than doing a
> simple
> conversion.
>
> Sam
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Thanks,

Tracey D