[OE-core] diff between defining a "no-op" task and using [noexec]?

[Robert P. J. Day]

On Fri, 18 Oct 2013, Richard Purdie wrote:

> On Fri, 2013-10-18 at 09:13 -0400, Robert P. J. Day wrote:

... snip ...

> >   i figured as much, but is there any important (pragmatic)
> > distinction between the two if one simply wants to nullify an
> > existing task?
>
> One is slightly more efficient since bitbake doesn't run it at all.
>
> >   if there's a defined task dependency of some kind, i can
> > certainly see how having a defined task consisting of a no-op
> > would behave differently from specifying to not run that task at
> > all, in terms of subsequent dependencies. does that distinction
> > come into play anywhere? is there an example in the OE source that
> > recognizes this?
>
> No, the way we use noexec tasks, we still have to ensure
> dependencies are recognised and built before the noexec task is
> skipped.

  ah, that answers that question.

> >   and WRT to how developers should code, is one of these
> > approaches considered better than the other? i've seen both
> > approaches used in recipe files, and i'm wondering simply about
> > coding style. thanks.
>
> noexec is newer, slightly more efficient and not used everywhere.
> The ":" notation is slightly more readable in some circumstances.
>
> You're looking for a "use X" type answer but I'm not giving one
> since sometimes one can make slightly more sense that the other and
> I don't want patches doing wholesale conversion from one to the
> other. I appreciate that is frustrating but like any things, hard
> and fast rules don't make sense, you should think about it.

  i'm good with all that, thanks.

rday
-- 

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

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