[yocto] Change in override behavior?

[Paul Eggleton]

On Fri, 29 Apr 2016 09:24:23 Gary Thomas wrote:
> On 2016-04-29 09:16, Paul Eggleton wrote:
> > On Fri, 29 Apr 2016 08:06:16 Gary Thomas wrote:
> >> On 2016-04-29 07:08, Paul Eggleton wrote:
> >>> On Fri, 29 Apr 2016 06:24:55 Gary Thomas wrote:
> >>>> I used to be able to use something like this:
> >>>>      VARIABLE = "xyz"
> >>>> 
> >>>> and maybe in a .bbappend use
> >>>> 
> >>>>      VARIABLE_mymachine = "xyzzy"
> >>>> 
> >>>> where 'mymachine' is in OVERRIDES, which resulted in
> >>>> 
> >>>>      VARIABLE = "xyzzy"
> >>>> 
> >>>> This doesn't seem to work the same today, what I get is
> >>>> 
> >>>>      VARIABLE = "xyz"
> >>>>      VARIABLE_mymachine = "xyzzy"
> >>>> 
> >>>> Has this changed (recently)?  Why?  How to I make use of overrides?
> >>>> 
> >>>> Note: I'm using the latest Poky master (a9b503b26) updated 2016-04-28
> >>> 
> >>> When you say this is what you're seeing, how are you checking this?
> >>> bitbake -e ? Which part of that output are you looking at?
> >>> 
> >>> You *will* now see VARIABLE_mymachine in bitbake -e output even if
> >>> "mymachine" is in OVERRIDES - that's because the overridden values stay
> >>> in the datastore instead of a "finalisation" step eliminating them, in
> >>> order to allow OVERRIDES to be changed dynamically (possibly multiple
> >>> times) and still get the datastore contents you expect. That change was
> >>> made in the 2.0 release (jethro). However That should not affect the
> >>> final value of VARIABLE if "mymachine" is in OVERRIDES however. Are you
> >>> sure you are seeing what you think you're seeing? If so, is the bbappend
> >>> in fact being applied? Because if what you describe was really happening
> >>> then pretty much the entire system would be broken. I just checked a
> >>> similar case here and I see the expected results.
> >> 
> >> Yes, I am using 'bitbake -e <recipe> | grep ^VARIABLE' to look at this.
> >> 
> >> In my main recipe, I have this:
> >>     SOME_OTHER_VARIABLE ?= "${MACHINE}"
> >> 
> >> and my .bbappend for that recipe has these lines:
> >>     SOME_OTHER_VARIABLE_my-target-A = "something-else1"
> >>     SOME_OTHER_VARIABLE_my-target-B = "something-else2"
> >> 
> >> and local.conf has
> >> 
> >>     MACHINE="my-target-B"
> >> 
> >> With Yocto 2.0 (Poky ceeb52a2544) I get this:
> >>     SOME_OTHER_VARIABLE = "something-else2"
> >>     SOME_OTHER_VARIABLE_my-target-A = "something-else1"
> >>     SOME_OTHER_VARIABLE_my-target-B = "something-else2"
> >> 
> >> With today's (Poky a9b503b26) I get this:
> >>     SOME_OTHER_VARIABLE = "my-target-B"
> >>     SOME_OTHER_VARIABLE_my-target-A = "something-else1"
> >>     SOME_OTHER_VARIABLE_my-target-B = "something-else2"
> >> 
> >> I also use this mechanism to set COMPATIBLE_MACHINE a lot and
> >> that doesn't seem to be working the same either.
> >> 
> >> Am I doing something incorrectly (and just got away with it for years)?
> >> 
> >> n.b. If you're interested, I can share the .bb/.bbappend files
> >> with you privately (I can't put them on the public list)
> > 
> > Ah, one thing... do your machine names have uppercase characters in them
> > (as your pseudo-examples above do)? If so that was a 2.1 change; anything
> > that is to be used as an override must now be lower case (so DISTRO,
> > MACHINE, etc.)
>
> Indeed, my machine names do have an upper case letter in them.
> Any suggestions for how to handle this (short of renaming everything which
> would be a HUGE chore)?

It's no longer supported I'm afraid, BitBake's datastore is now coded to 
expect lowercase for all override values. You say it's a huge chore but surely 
a grep -l | xargs -n1 sed -i would do it?

Cheers,
Paul

-- 

Paul Eggleton
Intel Open Source Technology Centre