[OE-core] why does sysfsutils-2.1.0.bb set S = "${WORKDIR}/sysfsutils-${PV}"?

[Robert P. J. Day]

On Fri, 23 Oct 2015, Paul Eggleton wrote:

> Hi Robert,
>
> On Friday 23 October 2015 08:02:11 Robert P. J. Day wrote:
> >   side note: the first in a small set of posts where i simply want to
> > clarify minor oddities i run across in oe-core, not because they have
> > any desperate need to be fixed, but more because when i'm teaching
> > courses in oe/yocto, i run across the occasional weirdness that
> > puzzles students, and forces me to try to explain it, and sometimes
> > the explanation is, "that's just silly." so here's the first one.
> >
> >   as i read in bitbake.conf, the default source directory for any
> > recipe is defined as:
> >
> >   S = "${WORKDIR}/${BP}"
> >
> > which suggests that, as long as processing a recipe ends up using that
> > value as the source directory, there is no need for a recipe to
> > redefine S. kind of obvious, no?
> >
> >   in the case of sysfsutils-2.1.0.bb, one sees the line:
> >
> > S = "${WORKDIR}/sysfsutils-${PV}"
> >
> > which, given the standard definitions for variables BP and PV, seems
> > to expand into precisely the default value given in bitbake.conf.
> >
> >   so, unless i'm missing something, is there any actual need for that
> > line in the sysfsutils recipe file? is there something more subtle
> > going on here that i don't understand?
>
> I don't think so, it appears that line goes way back to the initial
> population of the repository. Looks like we could just drop it.

  thanks for the clarification. i realize that stuff like this is
annoyingly pedantic for developers and expert users, but it's
*exactly* the kind of thing students in my classes occasionally point
out and ask me to explain, and i stand there looking kind of baffled,
muttering, "what the hell ..."

  i'm about to update all my courseware so i'll just collect as many
of those as i can find and submit as a single patch.

rday

-- 

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

Twitter:                                       http://twitter.com/rpjday
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