[yocto] Undefining a variable in a recipe?

[Otavio Salvador]

On Fri, May 2, 2014 at 10:35 AM, Alex J Lennon
<ajlennon at dynamicdevices.co.uk> wrote:
> I might be misunderstanding what you are saying here, but if you look at my
> earlier email, and check the patchbin snippets I provided you will see I am
> preferring 2009.08
>
> PREFERRED_VERSION_u-boot-imx="2009.08"
>
> The test in uboot-config.bbclass causes this to fail/be unavailable to the
> build, which is why the log says I cannot use 2009.08, instead falling back
> to the newer version. Removing the two lines checking for the definition of
> the two variables results in the 2009.08 build completing successfully - but
> I don't want to leave that little bomb in meta-fsl-arm for colleagues to
> fall over in future.

I think this should solve your issue. Please give this a try and I can
make a formal patch and send.

http://privatepaste.com/662e15c6b5

> I cannot override what meta-fsl-arm is setting because I can't (or don't
> know how to) undefine one of those two variables in my bbappend, and
> although I believe I _can_ set it to an empty string as  Paul suggested, I
> don't believe the the getVar() code in uboot-config.bbclass checks this,
> although I'm a bit unclear on the semantics of that function call.

I think this had been handled now, in the patch.

> I appreciate the help here Otavio, and I was hoping there was a simple
> non-invasive way to solve the problem by undefining the variable in my
> layer, as it seemed cleaner.
>
> I don't want to waste any more of your time on this though so if I can't do
> that then I'll  just  take the hacky route  as an intermediary step, copy
> out your 2009.08 recipe into my layer and mod it there.

Now I better understood your issue and you really found an issue in
the code. Please give this a try and confirm if it works for yu so I
can send the fix for review.

-- 
Otavio Salvador                             O.S. Systems
http://www.ossystems.com.br        http://code.ossystems.com.br
Mobile: +55 (53) 9981-7854            Mobile: +1 (347) 903-9750