Re: [PATCH v2 03/10] kbuild: allow architectures to override CC_CAN_LINK

[Nicolas Schier <nsc@kernel.org>]

On Tue, Oct 14, 2025 at 03:05:18PM +0200, Thomas Weißschuh wrote:
> The generic test for CC_CAN_LINK assumes that all architectures use -m32
> and -m64 to switch between 32-bit and 64-bit compilation. This is overly
> simplistic. Architectures may use other flags (-mabi, -m31, etc.) or may
> also require byte order handling (-mlittle-endian, -EL). Expressing all
> of the different possibilities will be very complicated and brittle.
> Instead allow architectures to supply their own logic which will be
> easy to understand and evolve.
> 
> Both the boolean ARCH_HAS_CC_CAN_LINK and the string ARCH_USERFLAGS need
> to be implemented as kconfig does not allow the reuse of string options.
> 
> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
> ---
>  Makefile     | 13 +++++++++++--
>  init/Kconfig |  4 ++++
>  2 files changed, 15 insertions(+), 2 deletions(-)
> 
> diff --git a/Makefile b/Makefile
> index 17cfa11ca7163aa3297101ceb3c9e85f4878f12d..26e5bca534e27034c355939bca4c90db435ecdbd 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -1134,8 +1134,17 @@ ifneq ($(CONFIG_ARCH_VMLINUX_NEEDS_RELOCS),)
>  LDFLAGS_vmlinux	+= --emit-relocs --discard-none
>  endif
>  
> -# Align the bit size of userspace programs with the kernel
> -USERFLAGS_FROM_KERNEL := -m32 -m64 --target=%
> +# Align the architecture of userspace programs with the kernel
> +USERFLAGS_FROM_KERNEL := --target=%
> +
> +ifdef CONFIG_ARCH_USERPROGS_CFLAGS

Is this some left-over from a previous version?

s/CONFIG_ARCH_USERPROGS_CFLAGS/CONFIG_ARCH_USERFLAGS/

Kind regards,
Nicolas