[yocto] Extending images

[Christopher Larson]

On Fri, Jul 18, 2014 at 9:26 AM, Gary Thomas <gary at mlbassoc.com> wrote:

> 've always used 'IMAGE_INSTALL += " xyz"' in my local.conf
> to add new packages to a build.  That said, I had a working
> build for qemuarm (probably doesn't matter) and I added:
>   IMAGE_INSTALL += " strace"
> This produced a completely broken image which barely came
> up to a shell, lots of missing programs, etc.
>
> I then tried
>   CORE_IMAGE_EXTRA_INSTALL += " strace"
> which produced a perfectly working build (just as previous)
> with the new package added.
>
> I can see that the images produced are vastly different:
>
> * Original working build
> -rw-r--r-- 1 gthomas gthomas     11719 Jul 18 09:34
> core-image-sato-qemuarm-20140718124453.rootfs.manifest
> -rw-r--r-- 1 gthomas gthomas  87611203 Jul 18 09:34
> core-image-sato-qemuarm-20140718124453.rootfs.tar.bz2
>
> * After 'IMAGE_INSTALL += '
> -rw-r--r-- 1 gthomas gthomas      9986 Jul 18 09:55
> core-image-sato-qemuarm-20140718155134.rootfs.manifest
> -rw-r--r-- 1 gthomas gthomas  37859884 Jul 18 09:56
> core-image-sato-qemuarm-20140718155134.rootfs.tar.bz2
>
> * After 'CORE_IMAGE_EXTRA_INSTALL += '
> -rw-r--r-- 1 gthomas gthomas     11738 Jul 18 10:05
> core-image-sato-qemuarm-20140718160108.rootfs.manifest
> -rw-r--r-- 1 gthomas gthomas  87720106 Jul 18 10:05
> core-image-sato-qemuarm-20140718160108.rootfs.tar.bz2
>
> What's the difference and why did the first attempt fail?
>

Most likely the image defined its own IMAGE_INSTALL using ?=, so defining
it yourself in the configuration data overrode its default definition,
since ?= is "set only if unset". If the recipe didn't use ?=, then your
IMAGE_INSTALL += would have had no effect at all. To append to
IMAGE_INSTALL directly without using CORE_IMAGE_EXTRA_INSTALL you could
have used IMAGE_INSTALL_append, since that's a postponed operation that
happens at the end of the recipe parsing.
-- 
Christopher Larson
clarson at kergoth dot com
Founder - BitBake, OpenEmbedded, OpenZaurus
Maintainer - Tslib
Senior Software Engineer, Mentor Graphics
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.yoctoproject.org/pipermail/yocto/attachments/20140718/2e26620c/attachment.html>