[yocto] Why did my build need to redo so many tasks?

[Burton, Ross]

On 12 February 2015 at 21:25, Gary Thomas <gary at mlbassoc.com> wrote:

> Yesterday, I built a large image using Poky/Yocto 870323cac1e
> Today I updated my Poky repo to 231d4a9d3
>
> When I rebuilt the same image, bitbake kicked off more than
> 5200 tasks, building virtually every package from scratch.
>
> How can I tell why this happened?  I don't have buildhistory
> enabled, but I do still have the tmp & sstate-cache trees
> from the process.  Is there enough info laying around that
> I can tell, e.g. why the GCC toolchain had to be rebuilt
> completely?
>
> Am I correct in assuming that bitbake-whatchanged is really
> a Quija board and can only tell me [in advance] what will need
> to be done if my layers change?  When I ran it after the long
> build above, it didn't really tell me much :-(
>

If you checkout the first commit, do a build, then the second commit and
run bitbake-whatchanged, it should tell you the difference.

Looking at the git log shows cc5f80, which is a change to libtool, so
everything inheriting autotools will need a rebuild.

Ross
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.yoctoproject.org/pipermail/yocto/attachments/20150212/c52e4897/attachment.html>