[OE-core] Problem with RDEPENDS in multimachine builds for allarch packages

[Richard Purdie]

On Tue, 2015-10-27 at 09:30 +0100, Mike Looijmans wrote:
> On 26-10-15 16:13, Sergey 'Jin' Bostandzhyan wrote:
> > Hi,
> >
> > I recently ran into a problem that I described here:
> > https://bugzilla.yoctoproject.org/show_bug.cgi?id=8578 and while debugging
> > this issue an other problem came to light.
> >
> > I have a multimachine configuration (armv5/imx6) and the same distro for both
> > of them (poky 2.0 RC based).
> >
> > I have some allarch packages which have no DEPENDS, however which have an
> > RDEPENDS_${PN} setting.
> >
> > I can see that even though there were no changes to the recipe itself and
> > also no changes to the recipes listed in RDEPENDS, my recipe still gets
> > rebuilt each time.
> >
> > What we tried:
> >
> > <bluelightning> so cleansstate the recipe, change machine, cleansstate again,
> >                  then build it, then change machine, build it again and note
> >                  the first task that executes
> >
> > The logs for these steps, one with RDEPENDS and one without are at the end of
> > this mail. I can see that with present RDEPENDS "real" tasks get executed
> > even though no changes occured in the recipe; this is not the case when I
> > drop RDEPENDS.
> >
> > Is this a bug or is this just something that needs to be documented?
> 
> I think it's the same problem as described here:
> http://thread.gmane.org/gmane.comp.handhelds.openembedded.core/70070/focus=70072
> 
> > What is the "desired" behaviour?
> 
> Apparently, this needless rebuilding is "desired".

Its more that we can't tell the difference between a case where it is
needless and a case where it is no. The system therefore rebuilds as if
it didn't, there would be cases where it should have rebuilt and did
not.

Cheers,

Richard