Parallel make bug in busybox

[Richard Purdie]

On Fri, 2016-08-12 at 16:53 +0200, Peter Korsgaard wrote:
> > > > > > "Richard" == Richard Purdie <rpurdie at rpsys.net> writes:
> 
>  > We (as in the Yocto Project/OpenEmbedded) do a lot of builds of
> busybox
>  > and one of the failures we've seen recently was:
> 
>  > https://autobuilder.yoctoproject.org/main/builders/poky-tiny/build
> s/908
>  > /steps/BuildImages/logs/stdio
> 
> Interesting. We afaik haven't seen that kind of build issues on the
> Buildroot autobuilders:
> 
> http://autobuild.buildroot.org/?reason=busybox-1.25.0
> http://autobuild.buildroot.org/?reason=busybox-1.24.1

I assume you run builds with parallel make (-j X) enabled?

> What is "recent'? Do you only see this with 1.24.1?

We've seen this issue once and its not happened again as yet however
looking at the $(MAKE) invocations, I am a bit worried. There doesn't
appear to be any guard against these trampling on each other, or at
least in the failure case, that seems to be what happened.

Once we run into an issue like this, they do tend to surface when we
least want them to, for example during release builds.

>  Do you apply any patches on top of 1.24.1?

Yes, this gives an idea (*.patch):
http://git.yoctoproject.org/cgit.cgi/poky/tree/meta/recipes-core/busybox/busybox_1.24.1.bb

Several are backports for CVEs or other issues. I can't see anything in
the patches which would change materially makefile dependencies though
and whilst that list looks long, most of it is configuration files or
backports.

Cheers,

Richard