[OE-core] Generating extensible SDK fails because of missing LAYERSERIES_CORENAMES

[Damien Riegel]

Hi,


When generating the extended SDK, my setup fails with the following
error:

  ERROR: Failed to generate filtered task list for extensible SDK:
  ERROR: bitbake failed:
  ERROR: Unable to start bitbake server

I digged into the issue and found out why bitbake doesn't
start.

bitbake thinks layers are incompatible because they define
LAYERSERIES_COMPAT but LAYERSERIES_CORENAMES is not set. So this check
in cookerdata.py fails [1].

The reason this check fails is that the core `meta` layer is not listed
in the generated BBLAYERS, because it's treated in a special way in
populate_sdk_ext.bbclass [2]. So as this layer is not listed in
BBLAYERS, the compatibility check fails and bitbake cannot start.


Shouldn't `meta` simply be added to BBLAYERS as any other layer? If not,
what is the proper way to solve my bug?

[1] https://github.com/openembedded/bitbake/blob/master/lib/bb/cookerdata.py#L397
[2] https://github.com/openembedded/openembedded-core/blob/master/meta/classes/populate_sdk_ext.bbclass#L208

Thank you,
-- 
Damien