[oe] [meta-oe][PATCH v2] libeigen: allow empty packages

[Vyacheslav Yurkov]

On Thu, Oct 4, 2018 at 10:34 AM Martin Jansa <martin.jansa at gmail.com> wrote:

> > If there's another way to solve this, I'm all ears. BTW, ceres-solver
> recipe itself has ALLOW_EMPTY_${PN} = "1" already. I believe the reason is
> the same as here.
>
> Use bitbake -g my-image-dev to find out what package is depending on
> libeigen package and fix it there. Are you sure it's (only) from
> ceres-solver? Isn't libeigen listed in my-image-dev as well?
>

That makes sense. Indeed it was. I removed it from the image and it worked
well! Thanks for the hint. Now the only dependency on libeigen is
ceres-solver.

Adding ALLOW_EMPTY here is just hiding the issue somewhere else. It makes
> sense when the package might be empty based on some configuration (e.g.
> PACKAGECONFIGs), but in general ALLOW_EMPTY is bad idea. It also allows end
> user to do "opkg install libeigen" and assuming he got something useful
> when it installs something, which isn't true he just wasted few bytes of
> storage for completely empty package.
>

I have a bit different use case. I don't use package manager :)
But the point of having it in the image was to automatically put libeigen
into generated SDK. I checked it again, and SDK still generates properly
with libeigen-dev included.


> And when you're there you can remove ALLOW_EMPTY from ceres-solver as well
> :).
>

I will check if RDEPENDS_${PN}-dev works with ceres-solver as well. If it
does, then the patch from me will come ;)

Thanks again,
Vyacheslav


>
> Cheers,
>
> On Thu, Oct 4, 2018 at 9:04 AM Vyacheslav Yurkov <uvv.mail at gmail.com>
> wrote:
>
>> Hi Martin,
>> Thanks for your comment. I did see discussion in the mailing list that
>> RDEPENDS_${PN}-dev is supposed to solve it, but it doesn't. To be fare, I
>> tried it again now:
>> - bitbake libeigen -c cleanall
>> - bitbake ceres-solver -c cleanall
>> - reverted my ALLOW_EMPTY_${PN} = "1" change
>> - bitbake my-image
>>
>> After last step I got:
>> ERROR: my-image-dev-1.0-r0 do_rootfs: libeigen not found in the feeds
>> (x86 corei7-64 core2-64 x86_64 noarch any all) in
>> /home/uvv/projects/yocto-x86/build/tmp/deploy/rpm.
>> ERROR: my-image-dev-1.0-r0 do_rootfs: This is often caused by an empty
>> package declared in a recipe's PACKAGES variable. (Empty packages are not
>> constructed unless ALLOW_EMPTY_<pkg> = '1' is used.)
>> ERROR: my-image-dev-1.0-r0 do_rootfs: Function failed: do_rootfs
>>
>> If there's another way to solve this, I'm all ears. BTW, ceres-solver
>> recipe itself has ALLOW_EMPTY_${PN} = "1" already. I believe the reason is
>> the same as here.
>>
>> Regards,
>> Vyacheslav
>>
>> On Wed, Oct 3, 2018 at 8:35 AM Martin Jansa <martin.jansa at gmail.com>
>> wrote:
>>
>>> On Wed, Oct 03, 2018 at 08:24:22AM +0200, Vyacheslav Yurkov wrote:
>>> > libeigen is header-only library.
>>> > All headers go into dev package, therefore the main package is empty.
>>> > Dependency on the dev package doesn't work, so you have to allow
>>> > empty package for build to succeed for recipes that depend on libeigen
>>> > (e.g. ceres-solver). Otherwise an error occurs that empty packages
>>> > are not allowed.
>>>
>>> I still don't understand what the issue is, there is already
>>> RDEPENDS_${PN}-dev = "" and similar for ${PN}-dbg.
>>>
>>> Creating empty libeigen package to satisfy dependency from ceres-solver
>>> doesn't really fix anything (just installs useless empty package on
>>> target).
>>>
>>> > Signed-off-by: Vyacheslav Yurkov <uvv.mail at gmail.com>
>>> > ---
>>> >  meta-oe/recipes-support/libeigen/libeigen_3.3.4.bb | 1 +
>>> >  1 file changed, 1 insertion(+)
>>> >
>>> > diff --git a/meta-oe/recipes-support/libeigen/libeigen_3.3.4.bb
>>> b/meta-oe/recipes-support/libeigen/libeigen_3.3.4.bb
>>> > index 31a42a9d6..a59320655 100644
>>> > --- a/meta-oe/recipes-support/libeigen/libeigen_3.3.4.bb
>>> > +++ b/meta-oe/recipes-support/libeigen/libeigen_3.3.4.bb
>>> > @@ -18,3 +18,4 @@ FILES_${PN}-dev = "${includedir}
>>> ${datadir}/eigen3/cmake ${datadir}/cmake/Module
>>> >  # ${PN} is empty so we need to tweak -dev and -dbg package
>>> dependencies
>>> >  RDEPENDS_${PN}-dev = ""
>>> >  RRECOMMENDS_${PN}-dbg = "${PN}-dev (= ${EXTENDPKGV})"
>>> > +ALLOW_EMPTY_${PN} = "1"
>>> > --
>>> > 2.17.0
>>> >
>>> > --
>>> > _______________________________________________
>>> > Openembedded-devel mailing list
>>> > Openembedded-devel at lists.openembedded.org
>>> > http://lists.openembedded.org/mailman/listinfo/openembedded-devel
>>>
>>> --
>>> Martin 'JaMa' Jansa     jabber: Martin.Jansa at gmail.com
>>>
>>
>>