Re: [PATCH v2 2/2] powerpc: Replace __ASSEMBLY__ with __ASSEMBLER__ in non-uapi headers

[Segher Boessenkool <segher@kernel.crashing.org>]

On Wed, Jun 11, 2025 at 07:55:45AM +0200, Thomas Huth wrote:
> On 10/06/2025 22.26, Segher Boessenkool wrote:
> >On Tue, Jun 10, 2025 at 06:01:28PM +0200, 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.
> >
> >And it should not, the kernel is not allowed to define any symbol
> >starting with two underscores at all!  Including __ASSEMBLER__ yes.
> 
> Right, I can add that in the next version, too.
> 
> >>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 on
> >>the __ASSEMBLER__ macro that is provided by the compilers now.
> >
> >"Now"?  This is true since at least 2003, and probably a lot longer
> >already.
> 
> Sorry, I've put the "now" into the wrong location ... it should rather be 
> in the first half of the sentence instead :-)

Ah :-)

So do you want to redefine this symbol (which is off-limits) at all?  Or
do you belief that the compiler will have already defined it (like has
been documented for forever-and-a-half already, and there never were
problems with it)?


Segher