[OE-core] ALLOW_EMPTY versus ALLOW_EMPTY_${PN}? a couple clarifications

[Robert P. J. Day]

On Fri, 6 Jul 2012, Marcin Juszkiewicz wrote:

> W dniu 06.07.2012 15:10, Robert P. J. Day pisze:
> >
> >   just trying to clarify the gory details of the ALLOW_EMPTY setting.
> > first, across several .bb files, there is a mixture of these two:
> >
> > ALLOW_EMPTY = "1"
> > ALLOW_EMPTY_${PN} = "1"
> >
> >   what's the difference?  what does the first one represent if you're
> > not specific?  does that cover *all* generated packages?
>
> Yes, first means "all packages may be empty"

  and just to be clear, that means not just the default packages
(regular, -dev, -doc, etc.) but all additional packages that might be
defined for that recipe?

> >   next, i assume there's no real value to hardcoding the package name,
> > as in:
> >
> > ./meta/recipes-multimedia/alsa/alsa-utils_1.0.25.bb:ALLOW_EMPTY_alsa-utils = "1"
> >
> > (i assume the above could have just used the standard "_${PN}",
> > right?)
>
> ${PN} should be in this case.

  i thought so, just wanted to be sure.  i'm collecting all these
oddities i run across and am compiling my version of an OE "style
guide", which will contain pedantic observations like:

* don't hard-code a package name if you can use ${PN} instead

and

* there's no point setting ${PR} to "r0" since that's the default

  little things like that.

rday

-- 

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Robert P. J. Day                                 Ottawa, Ontario, CANADA
                        http://crashcourse.ca

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