[oe] [PATCHv3 1/3] conf/layer.conf: Use .= for BBPATH and += for BBFILES

[Phil Blundell]

On Mon, 2011-05-09 at 07:48 -0700, raj.khem at gmail.com wrote:
> From: Khem Raj <raj.khem at gmail.com>
> 
> Provide additional commentary that should help a bit more

I'm still struggling slightly to understand why this patch is an
improvement.  As far as I can tell:

- the change from prepending to appending BBPATH will alter all the
priorities of the layers.  It isn't entirely obvious to me if (or why)
this is a good thing; and

- the change to the way that BBFILES is assigned doesn't make any
functional difference.  Is that just a cosmetic change?

Also:

> +# It really depends on order of the layers appearing in BBLAYERS
> +# variable in toplevel bblayers.conf file, where bitbake will search
> +# for .inc files and others where bitbake uses BBPATH since it will
> +# search the directories from first to last as specified in BBPATH
> +# Therefore if you want a given layer to be considered high priority
> +# for the .inc and .conf etc. then consider it adding at the beginning
> +# of BBPATH. For bblayers bitbake will use BBFILES_PRIORITY to resolve
> +# the recipe contention so the order of directories in BBFILES does 
> +# not matter.

Maybe it's just my lack of familiarity with the code, but I find this
comment rather difficult to parse.  Even after reading it a few times
I'm not totally sure that I've grasped what the first sentence is
saying.

p.