[yocto] BBMASK issue

[Peter Kjellerstedt]

> -----Original Message-----
> From: yocto-bounces at yoctoproject.org [mailto:yocto-bounces at yoctoproject.org] On Behalf Of Andre McCurdy
> Sent: den 23 augusti 2016 07:13
> To: Takashi Matsuzawa
> Cc: yocto at yoctoproject.org
> Subject: Re: [yocto] BBMASK issue
> 
> On Mon, Aug 22, 2016 at 6:50 PM, Takashi Matsuzawa <tmatsuzawa at uievolution.com> wrote:
> > Hello Yocto.
> >
> > Now I am trying to customize an existing BSP to my need.
> > For this, I am adding following to my local.conf so that some of 
> > the recipes in the BSP to be ignored.
> >
> > (local.conf)
> > BBMASK = "aaa|bbb|ccc"
> > BBMASK .= "|ddd|eee"
> >
> > However, it does not work since BSP itself has lines like below in
> > its layer.
> >
> > (somelayer.conf)
> > BBMASK = "xxx|yyy|xxx"
> >
> > The BSP definition of BBMASK seems to be overwriting my BBMASK
> > definition in my local.conf.
> > I wonder what is the best way so that the both definition are
> > effective.
> >
> > I confirmed modifying BSP's definition as below works, but not sure
> > if this can be recommended as practice to everyone who provides 
> > layers for their BSPs.
> >
> > BBMASK .= "|xxx|yyy|xxx"
> 
> This isn't safe. It will only work if a default value for BBMASK is
> set elsewhere. If not, then you end up with a BBMASK which begins with
> "|", which effectively masks _every_ recipe.

Please note that BBMASK was changed in Krogoth to allow multiple regular 
expressions (see commit a948f5252 in Poky). Basically, with Krogoth and 
later you can do:

BBMASK = "aaa bbb ccc"	
BBMASK += "ddd eee"
BBMASK_append = " fff ggg"

as with most other BitBake variables taking multiple values. Of course, 
it is still possible to use | as before if you really want to, but I 
recommend to avoid it if possible because of the problems mentioned 
above.

//Peter