[OE-core] curious about inherent value of dynamic layers

[Gary Thomas]

On 2016-11-01 11:18, Robert P. J. Day wrote:
>
>   more pedantry: i notice that a small number of layers (eg,
> meta-freescale, meta-mentor) include "dynamic" layers, so that some
> sublayers are included only conditionally if others layers are
> included. from meta-freescale's layer.conf:
>
> ///// start
>
>   # The dynamic-layers directory hosts the extensions and layer specific
>   # modifications related to Freescale products.
>   #
>   # The .bbappend and .bb files are included if the respective layer
>   # collection is available.
>   BBFILES += "${@' '.join('${LAYERDIR}/dynamic-layers/%s/recipes*/*/*.bbappend' % layer \
>                for layer in BBFILE_COLLECTIONS.split())}"
>   BBFILES += "${@' '.join('${LAYERDIR}/dynamic-layers/%s/recipes*/*/*.bb' % layer \
>                for layer in BBFILE_COLLECTIONS.split())}"
>
> ///// end
>
> where the "dynamic-layers" directory in that layer contains further
> recipe directories with .bbappend files related to other layers:
>
>   drwxrwxr-x. 3 rpjday rpjday 4096 Jun 26 06:36 browser-layer
>   drwxrwxr-x. 3 rpjday rpjday 4096 Jun 26 06:36 efl-layer
>   drwxrwxr-x. 3 rpjday rpjday 4096 Jun 26 06:36 filesystem-layer
>   drwxrwxr-x. 4 rpjday rpjday 4096 Jun 26 06:36 networking-layer
>   drwxrwxr-x. 6 rpjday rpjday 4096 Jun 26 06:36 openembedded-layer
>   drwxrwxr-x. 3 rpjday rpjday 4096 Jun 26 06:36 qt4-layer
>   drwxrwxr-x. 3 rpjday rpjday 4096 Jun 26 06:36 qt5-layer
>   drwxrwxr-x. 3 rpjday rpjday 4096 Jun 26 06:36 virtualization-layer
>
> seems like an interesting idea ... opinions on whether this is a
> useful approach? or possibly overly confusing? is this approach
> mentioned in any OE/YP doc?

It's very useful if they have .bbappend files in these directories
as that will cause problems building if you don't include the corresponding
layers.


-- 
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Gary Thomas                 |  Consulting for the
MLB Associates              |    Embedded world
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