[OE-core] Weird ALTERNATIVES and staging conflict.

[Richard Purdie]

On Mon, 2014-11-03 at 10:53 +0100, Mike Looijmans wrote:
> On 10/30/2014 06:47 PM, Richard Purdie wrote:
> > On Thu, 2014-10-30 at 15:17 +0100, Mike Looijmans wrote:
> >> I have this base script that builds FPGA bitstreams:
> >>
> >> https://github.com/topic-embedded-products/meta-topic/blob/master/recipes-bsp/fpga/fpga-image.inc
> >>
> >> Now you can have multiple recipes using it, and as such, it seemed a good idea
> >> to add these lines to that recipe:
> >>
> >> +ALTERNATIVE_${PN} = "fpga.bin bitstreams"
> >> +ALTERNATIVE_LINK_NAME[fpga.bin] = "${datadir}/fpga.bin"
> >> +ALTERNATIVE_TARGET[fpga.bin] = "${datadir}/fpga.bin"
> >> +ALTERNATIVE_LINK_NAME[bitstreams] = "${datadir}/bitstreams"
> >> +ALTERNATIVE_TARGET[bitstreams] = "${datadir}/bitstreams"
> >>
> >>
> >> This still resulted in staging conflicts.
> >
> > This isn't surprising since update-alternatives only works for target
> > systems. It is not designed for operating on the sysroot.
> 
> I don't want these files in sysroot, I want them on target only.

Ok, that makes things much easier.

> >> But looking at the contents of the fake packages, the fpga.bin has been
> >> renamed by alternatives (as expected), and the symlink will be created after
> >> installing, so how come I still get this?
> >
> > The "staging" code uses the output of do_install directly and does
> > different things to the packaging code path. We've never had someone
> > with this problem before. Binaries in *bindir only get installed into
> > the sysroot in the -native case.
> >
> > I appreciate that tells you why it doesn't work and not how to fix it
> > but hopefully that helps a bit.
> 
> If I understand you correctly, the problem is that the recipe is trying to 
> install things in sysroot?

Correct, by default ${datadir} is staged. The easiest way to handle this
may be to define your own sysroot_stage_all function (or
sysroot_stage_dirs) which just stages what you need, if anything.

Cheers,

Richard