Re: [PATCH v12 2/3] kbuild: change --thin back to 'T' in $(AR)

[Nicolas Schier <nsc@kernel.org>]

On Fri, May 29, 2026 at 11:53:45AM -0700, xur@google.com wrote:
> From: Rong Xu <xur@google.com>
> 
> The '-T' flag in $(AR) is no longer problematic since the minimum
> requirement for LLVM has been updated to version 15. As of LLVM 14
> and onward, the '-T' flag functions identically to the '--thin' flag.

For correctness: it's called "'T' modifier"  (instead of "'-T' flag").

> 
> Fixed the issue seen on IBM Power11 System:
>   ar: unrecognized option '--thin'
> 
> Reported-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
> Closes: https://lore.kernel.org/linux-next/476507c9-a371-4864-9e87-572c1ecae82d@linux.ibm.com/
> Signed-off-by: Rong Xu <xur@google.com>
> ---
>  scripts/Makefile.vmlinux_a | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/scripts/Makefile.vmlinux_a b/scripts/Makefile.vmlinux_a
> index 9774f02b43b2..650d44330d1f 100644
> --- a/scripts/Makefile.vmlinux_a
> +++ b/scripts/Makefile.vmlinux_a
> @@ -10,12 +10,12 @@ include $(srctree)/scripts/Makefile.lib
>  # Link of built-in-fixup.a
>  # ---------------------------------------------------------------------------
>  
> -# '$(AR) mPi' needs --thin to workaround the bug of llvm-ar <= 14
> +# '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14

This comment should be removed.

>  quiet_cmd_ar_builtin_fixup = AR      $@
>        cmd_ar_builtin_fixup = \
>  	rm -f $@; \
> -	$(AR) cDPrS --thin $@ $(KBUILD_VMLINUX_OBJS); \
> -	$(AR) mPi --thin $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
> +	$(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
> +	$(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
>  
>  targets += built-in-fixup.a
>  built-in-fixup.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt FORCE
> -- 
> 2.54.0.823.g6e5bcc1fc9-goog
> 

Thanks!

Reviewed-by: Nicolas Schier <nsc@kernel.org>