[yocto] sstate black hole?

[Gary Thomas]

On 2015-06-16 02:37, Paul Eggleton wrote:
> On Monday 15 June 2015 18:19:21 Gary Thomas wrote:
>> I followed this down to an i.MX6 specific package which is
>> in DEPENDS:
>>     Variable PROVIDES value changed from
>>     '${PN}  virtual/wayland-egl virtual/libgal-x11 virtual/egl
>> virtual/libopenvg virtual/libg2d virtual/libgl virtual/libgles1
>> virtual/libgles2' to
>>     '${PN}  virtual/wayland-egl virtual/libgal-x11 virtual/egl
>> virtual/libopenvg virtual/libg2d virtual/libgl virtual/libgles1
>> virtual/libgles2 virtual/libgl virtual/libgles1 virtual/libgles2'
>>
>> Why aren't these considered the same (duplicate elements and/or order)
>> should not matter for PROVIDES.  Is there some way we could get bitbake
>> to collapse this and remove the duplicates?
>>
>> I found that this happens in
>> meta-fsl-arm:recipes-graphics/imx-gpu-viv/imx-gpu-viv.inc which contains
>> these lines:
>>     PROVIDES += "virtual/wayland-egl virtual/libgal-x11 virtual/egl
>> virtual/libopenvg virtual/libg2d"
>> PROVIDES_append_mx6q  = " virtual/libgl virtual/libgles1 virtual/libgles2"
>> PROVIDES_append_mx6dl  = " virtual/libgl virtual/libgles1 virtual/libgles2"
>> PROVIDES_append_mx6sx  = " virtual/libgl virtual/libgles1 virtual/libgles2"
>>
>> Some i.MX6 targets, nitrogen6x in particular, has overrides for both mx6q
>> and mx6dl, hence the duplication.
>>
>> Note: I removed the extra override (for testing) and found that
>> now the packages built by target A can be shared via sstate with
>> target B (at least the few I tested)
>
> I agree this would be nice, but for this to work we'd probably need to
> introduce a typing system within bitbake so that it can understand that this
> variable is a space-separated list. That is something we will probably do at
> some point for a variety of reasons, but I don't know that it's something we
> will get to soon.

Is there some way to solve this in the recipe itself?  I can see that
it needs to make sure that those values are provided for each of the
[sub]class of processor, but is there a way to write it so that they
are only added once?  Perhaps a little bit of Python magic?

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