Re: [PATCH] xen/arm: Replace __ASSEMBLY__ with __ASSEMBLER__ in interface.h

Stefano Stabellini
2026-04-21T22:15:47Z

On Tue, 21 Apr 2026, Thomas Huth wrote:
> From: Thomas Huth <thuth@redhat.com>
>
> While the GCC and Clang compilers already define __ASSEMBLER__
> automatically when compiling assembly code, __ASSEMBLY__ is a
> macro that only gets defined by the Makefiles in the kernel.
> This can be very confusing when switching between userspace
> and kernelspace coding, or when dealing with uapi headers that
> rather should use __ASSEMBLER__ instead. So let's standardize now
> on the __ASSEMBLER__ macro that is provided by the compilers.
>
> Signed-off-by: Thomas Huth <thuth@redhat.com>

I haven't been closely following the __ASSEMBLER__ vs __ASSEMBLY__
discussion. If there is general agreement to use __ASSEMBLER__ in
headers, I am happy to go along with that. Currently, I see more than
140 uses of __ASSEMBLY__ compared to fewer than 20 uses of
__ASSEMBLER__, but I'll defer to your judgment if the project is moving
in that direction.

> ---
> Note: This patch has been split from an earlier patch series of mine
> to ease reviewing.
>
> include/xen/arm/interface.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/include/xen/arm/interface.h b/include/xen/arm/interface.h
> index c3eada2642aa9..61360b89da405 100644
> --- a/include/xen/arm/interface.h
> +++ b/include/xen/arm/interface.h
> @@ -30,7 +30,7 @@
>
> #define __HYPERVISOR_platform_op_raw __HYPERVISOR_platform_op
>
> -#ifndef __ASSEMBLY__
> +#ifndef __ASSEMBLER__
> /* Explicitly size integers that represent pfns in the interface with
> * Xen so that we can have one ABI that works for 32 and 64 bit guests.
> * Note that this means that the xen_pfn_t type may be capable of
> --
> 2.53.0
>