Re: [PATCH] scripts: headers_install.sh: Normalize __ASSEMBLY__ to __ASSEMBLER__

[Nathan Chancellor]

On Mon, Mar 09, 2026 at 04:58:11PM +0100, Thomas Weißschuh wrote:
> There is an ongoing effort to replace the usage of __ASSEMBLER__ with
> __ASSEMBLY__ throughout the kernel tree, see for example

I think __ASSEMBLER__ and __ASSEMBLY__ are swapped here?

> commit 287d163322b7 ("arm64: Replace __ASSEMBLY__ with __ASSEMBLER__ in
> non-uapi headers"). The latter is automatically provided by all compilers
> and preprocessors supported by the kernel, so the explicit definitions
> of __ASSEMBLER__ can be removed.
> 
> However the UAPI headers might be used with older (< GCC 3.0) or
> non-GCC-compatible compilers, which do not define __ASSEMBLY__

__ASSEMBLER__?

> automatically. So this migration may brake users.

It sounds like the "< GCC 3.0" part of that might not be true based on
Maciej's research?

  https://lore.kernel.org/alpine.DEB.2.21.2603101412520.63708@xxxxxxxxxxxxxxxxx/

> Also during the migration phase, the UAPI headers will use a mix of
> *both* __ASSEMBLY__ and __ASSEMBLER__ at the same time, which is ugly.
> 
> For now make sure that the exported UAPI headers consistently use
> __ASSEMBLER__ as before.

__ASSEMBLY__?

> Link: https://lore.kernel.org/lkml/164baf81-2824-4943-bbc1-4ae8a160c0cc@xxxxxxxx/
> Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
> ---
> This should go either through kbuild or asm-generic, I think.
> ---
>  scripts/headers_install.sh | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/scripts/headers_install.sh b/scripts/headers_install.sh
> index 9c15e748761c..2f1d1767ca26 100755
> --- a/scripts/headers_install.sh
> +++ b/scripts/headers_install.sh
> @@ -36,6 +36,7 @@ sed -E -e '
>  	s/(^|[^a-zA-Z0-9])__packed([^a-zA-Z0-9_]|$)/\1__attribute__((packed))\2/g
>  	s/(^|[[:space:](])(inline|asm|volatile)([[:space:](]|$)/\1__\2__\3/g
>  	s@#(ifndef|define|endif[[:space:]]*/[*])[[:space:]]*_UAPI@#\1 @
> +	s/__ASSEMBLY__/__ASSEMBLER__/g

It seems like this does the opposite of what is intended or am I
misunderstanding something here?

>  ' $INFILE > $TMPFILE || exit 1
>  
>  scripts/unifdef -U__KERNEL__ -D__EXPORTED_HEADERS__ $TMPFILE > $OUTFILE
> 
> ---
> base-commit: 6de23f81a5e08be8fbf5e8d7e9febc72a5b5f27f
> change-id: 20260302-uapi-assembly-0bb7213b41f1
> 
> Best regards,
> -- 
> Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
>