Re: [OE-core] [PATCH v5 07/15] kernel-yocto.bbclass: Disable ccache when rust-kernel is enabled

Yoann Congal
2026-02-10T15:25:05Z

On Wed Feb 4, 2026 at 2:07 PM CET, Yoann Congal wrote:
> Le mer. 4 févr. 2026 à 13:34, Richard Purdie <
> richard.purdie@linuxfoundation.org> a écrit :
>
>> On Wed, 2026-02-04 at 13:31 +0100, Yoann Congal wrote:
>> > On Wed Feb 4, 2026 at 1:05 PM CET, Paul Barker wrote:
>> > > On Thu, 2026-01-29 at 08:39 -0800, Sadineni, Harish via
>> > > lists.openembedded.org wrote:
>> > > > From: Yoann Congal <yoann.congal@smile.fr>
>> > > >
>> > > > Currently, a ccache enabled build fails with:
>> > > > | HOSTRUSTC scripts/generate_rust_target
>> > > > | HOSTCC scripts/kallsyms
>> > > > | HOSTCC scripts/sorttable
>> > > > | HOSTCC scripts/asn1_compiler
>> > > > | TOUCH include/generated/gcc-plugins.h
>> > > > | DESCEND objtool
>> > > > | error: multiple input filenames provided (first two filenames
>> are gcc and
>> > > >
>> .../tmp/work-shared/qemux86-64/kernel-source/scripts/generate_rust_target.rs)
>> > > >
>> > > > when using ccache, value of "HOSTCC=cache gcc" when this value is
>> passing
>> > > > to rustc, It is thinking gcc is a input file. when ccache is not
>> used "HOSTCC=gcc" is passed.
>> > > >
>> > > > Disable ccache for kernel build if rust-kernel is enabled to
>> workaround
>> > > > this.
>> > > >
>> > > > Signed-off-by: El Mehdi YOUNES <elmehdi.younes@smile.fr>
>> > > > Signed-off-by: Yoann Congal <yoann.congal@smile.fr>
>> > > > Signed-off-by: Harish Sadineni <Harish.Sadineni@windriver.com>
>> > >
>> > > This patch is good, but we should try to get the issue resolved
>> upstream
>> > > if we can so that ccache can be used.
>> > >
>> > > Has this been reported upstream yet? Could you also open a bug in our
>> > > bugzilla to track this?
>> >
>> > Hello,
>> >
>> > For context, a lengthy discussion happened on this patch here:
>> >
>> https://lore.kernel.org/openembedded-core/CA+TGqK9Yd2WWKrhMkhofF-8N0cESCSefWD2DXr4sBO9fDQXyrg@mail.gmail.com/t/#u
>> >
>> > And, sadly, we lack resources at the moment on our side to follow-up on
>> this :-/
>>
>> Putting some links alongside this to more details would probably at
>> least help a bit, particularly if ccache upstream documents it is
>> imcompatible with rust...
>>
>
> Ok, I'll send a more documented patch to Harish for him to integrate in his
> next iteration.

I pushed a branch on contrib (v5 + this commit modified)
https://git.openembedded.org/openembedded-core-contrib/log/?h=ycongal/kernel-rust

The modified commit is:
https://git.openembedded.org/openembedded-core-contrib/commit/?h=ycongal/kernel-rust&id=794bdad82933ee112452c8c08c917cf235e07ada

Harish, are you OK taking this for your next iteration?

Regards,
--
Yoann Congal
Smile ECS