Re: [PATCH] dpkg: Add support for building packages also for multi archs

[Jan Kiszka <jan.kiszka@siemens.com>]

On 16.01.23 12:50, Koch, Stefan (DI PA DCP R&D 3) wrote:
> Sounds principally good. Thanks.
> 
> For the kbuild case I have submitted a similar patch:
> [PATCH v2 3/5] dpkg: Add support for additional target and host builds
> (Tue, 20 Dec 2022 18:09:19 +0100)
> 
> It modifies dpkg-base.bbclass instead of dpkg.bbclass
> 
> It uses the SBUILD_HOST variable for the same purpose as this patch
> fulfills with the new PACKAGE_ARCH(S) variable. Migration from
> SBUILD_HOST to PACKAGE_ARCHS should be possible. But I have not tested
> this yet.
> 
> My patch will additionally set SCHROOT_DIR depending on
> ISAR_CROSS_COMPILE to SCHROOT_TARGET_DIR or SCHROOT_HOST_DIR. That's
> what I have not found inside this patch.

It's not needed in my model because schroot variations collapse if you
don't need them (host=target), and the host variant can not only build
for the target but naturally also the host - thus SCHROOT_HOST is
universal in practice.

> Since my patch does it in the
> dpkg-base.bbclass the schroot configuration is written before running
> dpkg_runbuild with the correct SCHROOT_DIR. Doing this in dpkg.bbclass
> would need a bit more code - it's not impossible I think.

There is in fact a 3rd proposal that Adriaan explained to me on Friday
(not sure if he shared it on the list before), and that would model the
variation via different (auto-generated) targets (mytarget,
mytarget-native, mytarget-compat). It has some critical point regarding
how to detect non-identical rebuilt arch-all and source packages, but
would otherwise be even more elegant. Adriaan wants to follow-up on that
soon.

Jan

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