[OE-core] ASSUME_PROVIDED versus SANITY_REQUIRED_UTILITIES versus "The Build Host Packages"

[Richard Purdie]

On Mon, 2016-11-28 at 06:20 -0500, Robert P. J. Day wrote:
>   a bit confused by what i'm seeing in a recent
> qemuppc/core-image-minimal build on my fedora system regarding which
> native packages are built, despite what's in bitbake.conf (using
> current poky layer checkout).
> 
>   first, here's a snippet from bitbake.conf:
> 
>   ASSUME_PROVIDED = "\
>     bzip2-native \          <---
>     chrpath-native \
>     file-native \           <---
>     findutils-native \
>     git-native \
>     grep-native \
>     diffstat-native \
>     ... snip ...
> 
> suggesting that (among other things) bzip2-native and file-native
> shouldn't be built -- it's the developer's responsibility to install
> them, yes? but if i peek under tmp/work/x86_64-linux, i can see:

There are two ways "file-native" can be used in a build. It can be used
as the host provided "file" command and it is also needed by the file
recipe to build file for the target. We need to build file-native in
order for the build for the target file command to build/work. This is
why it gets built.

With bzip2, we need libbz2 (native) during the build process and we
don't ASSUME_PROVIDED libbz2-devel, hence it builds bzip2-native only
for that piece. Confusing perhaps but necessary unfortunately.

Cheers,

Richard