Re: [PATCH v3 2/2] kconfig: Remove the architecture specific config for Propeller

[Rong Xu]

On Tue, Jun 2, 2026 at 2:43 AM Will Deacon <will@xxxxxxxxxx> wrote:
>
> On Mon, Jun 01, 2026 at 11:18:27AM -0700, Rong Xu wrote:
> > On Fri, May 29, 2026 at 5:47 PM Nathan Chancellor <nathan@xxxxxxxxxx> wrote:
> > > On Wed, 27 May 2026 14:45:08 -0700, xur@xxxxxxxxxx <xur@xxxxxxxxxx> wrote:
> > > > diff --git a/arch/Kconfig b/arch/Kconfig
> > > > index e510c585ea84..e4eaca9c917c 100644
> > > > --- a/arch/Kconfig
> > > > +++ b/arch/Kconfig
> > > > @@ -879,12 +879,8 @@ config AUTOFDO_CLANG
> > > >
> > > >         If unsure, say N.
> > > >
> > > > -config ARCH_SUPPORTS_PROPELLER_CLANG
> > > > -     bool
> > > > -
> > > >  config PROPELLER_CLANG
> > > >       bool "Enable Clang's Propeller build"
> > > > -     depends on ARCH_SUPPORTS_PROPELLER_CLANG
> > >
> > > It does not look like '' or its predecessor,
> > > '-fbasic-block-sections=labels', are supported by all architectures?
> > > This will break allmodconfig for some architectures in that case, so
> > > this needs to addressed with some other dependency.
> >
> > Thanks for catching this. Yes. -fbasic-block-address-map currently
> > only supports Arm64 and X86_64 as of now.
> > We thought people would only enable this config if they knew Propeller
> > was supported on that architecture.
> > But the allmodconfig build breaks this assumption.  I think I have to
> > keep this config for propeller, and make arm64 opt-in.
> >
> > >
> > >   | $ make -skj"$(nproc)" ARCH=arm LLVM=1 mrproper allmodconfig all
> > >   | ...
> > >   | clang: error: unsupported option '-fbasic-block-address-map' for target 'armv6k-unknown-linux-gnueabi'
> > >   | ...
> > >   |
> > >   | $ make -skj"$(nproc)" ARCH=s390 LLVM=1 mrproper allmodconfig all
> > >   | ...
> > >   | clang: error: unsupported option '-fbasic-block-address-map' for target 's390x-unknown-linux-gnu'
> > >   | ...
> > >
> > > Maybe something like
> > >
> > >   depends on CC_IS_CLANG && $(cc-option,-fbasic-block-address-map)
> > >
> > > then cleaning up scripts/Makefile.propeller to use it exclusively?
> >
> > I think keep ARCH_SUPPORTS_PROPELLER_CLANG is cleaner.
>
> I still don't think it has anything to do with the arch. If the compiler
> supports the option, then we can use it. The arch code in the kernel
> doesn't need to do anything, right? So can you just check if the
> compiler accepts the option using a 'depends on $(cc-option, ...)' line?

Yes, arch code in the kernel does not need to do anything—it is just a marker.

I understand your concern. I can use (cc-options,...) in PROPELLER_CLANG config.
But I will not use -fbasic-block-address-map for backward compatiliby reason.
I would use "-fbasic-block-sections=list=/dev/null".

I'll send the updated patch shortly.

Thanks,

-Rong

>
> Will