[oe] USE flags mumbling

[Chris Larson]

On Thu, Jul 1, 2010 at 3:16 PM, Tom Rini <tom_rini at mentor.com> wrote:

> Koen Kooi wrote:
>
>> -----BEGIN PGP SIGNED MESSAGE-----
>> Hash: SHA1
>>
>> On 01-07-10 18:24, Graeme Gregory wrote:
>>
>>> We already have BBCLASSEXTENDS which modifies ${PN} of a package and
>>> can use overrides to change behaviors of recipes.
>>>
>>> Maybe USE flags could be implemented in a similar fashing.
>>>
>>> DISTRO_USE = "nossl nox11"
>>>
>>> EXTRA_OECONF_append_use-nossl = "--disable-ssl"
>>>
>>> ${PN} of the recipe becomes XXXX-nossl
>>>
>>> Thoughts?
>>>
>>
>> Just that USE flags shouldn't be used if seperate recipes can solve it
>> as well.
>>
>
> If I may, I'd like to articulate what I believe to be the technical
> argument behind this statement.
>
> One of the issues with some form of USE flags, and I believe this is one of
> the big ones for Angstrom as well as any other public feed publishing
> distribution is that having a single recipe that does different things based
> on variables makes maintaining their feed (and allowing users to publish
> their own compatible feeds) a nightmare.
>
> This is because there isn't any form of use flag checking (a simple case of
> 1:1 or the more complex case of flagA needs flagB and flagC doesn't care
> about flagD -> flagZ).


Hmm, good point, dealing with dependency between recipes with specific flags
set or unset gets ugly fast.  *ponders*
-- 
Christopher Larson
clarson at kergoth dot com
Founder - BitBake, OpenEmbedded, OpenZaurus
Maintainer - Tslib
Senior Software Engineer, Mentor Graphics