[yocto] Invalidating tasks

[Alexander Kanavin]

On 11/29/2017 11:29 AM, Anton Gerasimov wrote:
> I've got two tasks, `do_A` and `do_B` (they are really IMAGE_CMDs if
> it's important). Now I want to introduce a third task,
> `do_check_A_and_B`, that will test that `do_A` and `do_B` have produced
> a correct result. If the test fails, I want to invalidate results of A
> and B, so that they re-run next time I run `bitbake some-image`. Is it
> possible? I've seen some "invalidate_task" functions in bb.siggen and in
> bb.runqueue, but I'm not sure about how to use them in a recipe/bbclass.

That would be a gross hack that goes against bitbake philosophy - which 
is that once a task completes successfully, you never need to re-run it 
again, unless the task content (or its dependencies) changes.

What are you doing in do_A and do_B, and why the outcome can vary 
without the tasks themselves changing? Are you fetching something from 
the network?

Alex