[yocto] Questioning FILESOVERRIDES implied precedence in setting FILESPATH...

[Richard Purdie]

On Mon, 2014-12-01 at 01:00 -0500, Bob Cochran wrote:
> In poky master, FILESOVERRIDES is constructed as follows:
> 
> "${TRANSLATED_TARGET_ARCH}:${MACHINEOVERRIDES}:${DISTROOVERRIDES}"
> 
> For my current build, I get:
> 
> FILESOVERRIDES="powerpc:custom-machine:e500v2:qoriq-ppc:poky"
> 
> FILESPATH is built by calling base_set_filespath(), which is in 
> utils.bbclass
> 
> This function constructs FILESPATH in such a way that the distro folder 
> ("poky") comes before the other overrides ( precedence is applied right 
> to left using FILESOVERRIDES )
> 
> I see that there was a patch to reverse the ordering back in Oct of 2013 
> (0bd63125c3b44) to make sure MACHINE overrides had precedence over 
> platform specific overrides.  However, I'm wondering if the intent was 
> to have the distro override both.  This doesn't make sense to me, so 
> please clarify whether this is correct.  If it is, please explain why 
> distro gets a higher precedence over machine.

It is intentional, the concept is that the distro is the ultimate
authority on configuration and it should be able to override anything,
including machine specific choices. I would agree that can work well in
some cases and less well in others.

Cheers,

Richard