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From:   Nick Desaulniers <ndesaulniers@google.com>
Date:   Wed, 5 Dec 2018 09:47:32 -0800
Message-ID: <CAKwvOdkMbf-=aKrWPZ7nPP0miKDxKMDYN4Kk46N4rxOwHb-zAw@mail.gmail.com>
Subject: Re: [PATCH 1/2] ARM: Remove '-p' from LDFLAGS
To:     Nathan Chancellor <natechancellor@gmail.com>
Cc:     linux@armlinux.org.uk,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Stefan Agner <stefan@agner.ch>,
        Nicolas Pitre <nicolas.pitre@linaro.org>,
        Ard Biesheuvel <ard.biesheuvel@linaro.org>
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On Tue, Dec 4, 2018 at 5:42 PM Nathan Chancellor
<natechancellor@gmail.com> wrote:
>
> This option is not supported by lld:
>
>     ld.lld: error: unknown argument: -p
>
> This has been a no-op in binutils since 2004 (see commit dea514f51da1 in
> that tree). Given that the lowest officially supported of binutils for
> the kernel is 2.20, which was released in 2009, nobody needs this flag
> around so just remove it. Commit 1a381d4a0a9a ("arm64: remove no-op -p
> linker flag") did the same for arm64.

While investigating the context of 1a381d4a0a9a for review, I found
that bfd had removed -p's implementation a long time ago, but kept the
flag as a no-op for compatibility.  I asked that the patch be extended
to arm as well, but don't think a v2 was ever cut.

Thanks for sending this Nathan.
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>

>
> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
> ---
>  arch/arm/Makefile                 | 2 +-
>  arch/arm/boot/compressed/Makefile | 2 --
>  2 files changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/arch/arm/Makefile b/arch/arm/Makefile
> index 05a91d8b89f3..e2a0baf36766 100644
> --- a/arch/arm/Makefile
> +++ b/arch/arm/Makefile
> @@ -10,7 +10,7 @@
>  #
>  # Copyright (C) 1995-2001 by Russell King
>
> -LDFLAGS_vmlinux        :=-p --no-undefined -X --pic-veneer
> +LDFLAGS_vmlinux        := --no-undefined -X --pic-veneer
>  ifeq ($(CONFIG_CPU_ENDIAN_BE8),y)
>  LDFLAGS_vmlinux        += --be8
>  KBUILD_LDFLAGS_MODULE  += --be8
> diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile
> index 1f5a5ffe7fcf..dcd07bd24b85 100644
> --- a/arch/arm/boot/compressed/Makefile
> +++ b/arch/arm/boot/compressed/Makefile
> @@ -131,8 +131,6 @@ endif
>  ifeq ($(CONFIG_CPU_ENDIAN_BE8),y)
>  LDFLAGS_vmlinux += --be8
>  endif
> -# ?
> -LDFLAGS_vmlinux += -p
>  # Report unresolved symbol references
>  LDFLAGS_vmlinux += --no-undefined
>  # Delete all temporary local symbols
> --
> 2.20.0.rc1
>


-- 
Thanks,
~Nick Desaulniers