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From: Nick Desaulniers <ndesaulniers@google.com>
Date: Mon, 11 Mar 2024 09:21:06 -0700
Message-ID: <CAKwvOdkGALie1d6oNXKNT8vwGmHbymsQ-dv-i0U_SQGFrhEJew@mail.gmail.com>
Subject: Re: [PATCH v1 13/13] tools headers: Rename noinline to __noinline
To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Ian Rogers <irogers@google.com>, Arnd Bergmann <arnd@arndb.de>, 
	Andrii Nakryiko <andrii@kernel.org>, Alexei Starovoitov <ast@kernel.org>, 
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On Mon, Mar 11, 2024 at 8:44=E2=80=AFAM Michael S. Tsirkin <mst@redhat.com>=
 wrote:
>
> On Sat, Mar 09, 2024 at 06:05:08PM -0800, Ian Rogers wrote:
> > An issue was reported with clang and llvm libc where the noinline
> > attribute [1] was being expanded due to the #define in
> > linux/compiler.h (now in compiler_attributes.h). The expansion caused
> > the __attribute__ to appear twice and break the build. To avoid this
> > conflict, rename noinline to __noinline which is more consistent with
> > other compiler attributes.
> >
> > [1] https://clang.llvm.org/docs/AttributeReference.html#noinline
>
> Following this link, I don't see __noinline there - only __noinline__ and
> noinline. What's up?

__noinline (which is what this patch is changing the preprocessor
define to) will not be expanded in the presence of
__attribute__((__noinline__)), __attribute__((noinline)), or
[[gnu::inline]], unlike the previous macro definition.

--=20
Thanks,
~Nick Desaulniers