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

[Gary Thomas]

On 2015-02-12 14:33, Burton, Ross wrote:
>
> On 12 February 2015 at 21:25, Gary Thomas <gary at mlbassoc.com <mailto: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.

Ouch, thanks.  Next time I'll know a bit more on how to diagnose this.

-- 
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Gary Thomas                 |  Consulting for the
MLB Associates              |    Embedded world
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