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From:   Sedat Dilek <sedat.dilek@gmail.com>
Date:   Mon, 19 Aug 2019 20:01:03 +0200
Message-ID: <CA+icZUVvkz2AK6KMdQrOrCvuzUc=6jrQYRzzLk+=CSDY=ezKMA@mail.gmail.com>
Subject: Re: [PATCH 16/16] compiler_attributes.h: add note about __section
To:     Nick Desaulniers <ndesaulniers@google.com>
Cc:     akpm@linux-foundation.org, jpoimboe@redhat.com, yhs@fb.com,
        Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>,
        Clang-Built-Linux ML <clang-built-linux@googlegroups.com>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Martin KaFai Lau <kafai@fb.com>,
        Song Liu <songliubraving@fb.com>, linux-kernel@vger.kernel.org,
        netdev@vger.kernel.org, bpf@vger.kernel.org
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On Mon, Aug 12, 2019 at 11:53 PM Nick Desaulniers
<ndesaulniers@google.com> wrote:
>
> The antipattern described can be found with:
> $ grep -e __section\(\" -r -e __section__\(\"
>
> Link: https://bugs.llvm.org/show_bug.cgi?id=42950
> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>

Tested-by: Sedat Dilek <sedat.dilek@gmail.com> [ Linux v5.3-rc5 ]

Patchset "for-5.3/x86-section-name-escaping":

include/linux/compiler.h: remove unused KENTRY macro
include/linux: prefer __section from compiler_attributes.h
include/asm-generic: prefer __section from compiler_attributes.h
x86: prefer __section from compiler_attributes.h

Thanks.

- Sedat -

> ---
>  include/linux/compiler_attributes.h | 10 ++++++++++
>  1 file changed, 10 insertions(+)
>
> diff --git a/include/linux/compiler_attributes.h b/include/linux/compiler_attributes.h
> index 6b318efd8a74..f8c008d7f616 100644
> --- a/include/linux/compiler_attributes.h
> +++ b/include/linux/compiler_attributes.h
> @@ -225,6 +225,16 @@
>  #define __pure                          __attribute__((__pure__))
>
>  /*
> + *  Note: Since this macro makes use of the "stringification operator" `#`, a
> + *        quoted string literal should not be passed to it. eg.
> + *        prefer:
> + *        __section(.foo)
> + *        to:
> + *        __section(".foo")
> + *        unless the section name is dynamically built up, in which case the
> + *        verbose __attribute__((__section__(".foo" x))) should be preferred.
> + *        See also: https://bugs.llvm.org/show_bug.cgi?id=42950
> + *
>   *   gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-section-function-attribute
>   *   gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attributes.html#index-section-variable-attribute
>   * clang: https://clang.llvm.org/docs/AttributeReference.html#section-declspec-allocate
> --
> 2.23.0.rc1.153.gdeed80330f-goog
>