Re: [PATCH v4 1/5] kbuild: add CONFIG_LD_IS_LLD

From: Nathan Chancellor <natechancellor@gmail.com>
To: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
	Masahiro Yamada <masahiroy@kernel.org>,
	linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org,
	Clang-Built-Linux ML <clang-built-linux@googlegroups.com>,
	linux-kbuild@vger.kernel.org,
	Nick Desaulniers <ndesaulniers@google.com>,
	Fangrui Song <maskray@google.com>,
	Sami Tolvanen <samitolvanen@google.com>,
	Dmitry Golovin <dima@golovin.in>
Subject: Re: [PATCH v4 1/5] kbuild: add CONFIG_LD_IS_LLD
Date: Wed, 29 Apr 2020 20:05:48 -0700	[thread overview]
Message-ID: <20200430030548.GA3546299@ubuntu-s3-xlarge-x86> (raw)
In-Reply-To: <CA+icZUXa3JBittjDVdNyV1M08dRt_pwACi2-0nLPEwao6yNABw@mail.gmail.com>

On Wed, Apr 29, 2020 at 09:13:40AM +0200, Sedat Dilek wrote:
> On Wed, Apr 29, 2020 at 12:14 AM Nathan Chancellor
> <natechancellor@gmail.com> wrote:
> >
> > From: Sami Tolvanen <samitolvanen@google.com>
> >
> > Similarly to the CC_IS_CLANG config, add LD_IS_LLD to avoid GNU ld
> > specific logic such as ld-version or ld-ifversion and gain the
> > ability to select potential features that depend on the linker at
> > configuration time such as LTO.
> >
> > Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
> > Acked-by: Masahiro Yamada <masahiroy@kernel.org>
> > [nc: Reword commit message]
> > Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
> 
> Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
> Reviewed-by: Sedat Dilek <sedat.dilek@gmail.com>
> 
> Testing on Debian/testing AMD64 (since Linux v5.3):
> #1: LLVM/Clang/LLD version 9.0 and 10.0
> #2: Debian's GCC 9.3 with ld.lld-9 and ld.lld-10
> 
> I am linking my Linux-kernels with ld.lld despite there are issues -
> then check with ld.bfd.

What issues are these? Have they been reported?

Cheers,
Nathan

> - Sedat -
> 
> > ---
> >
> > v3 -> v4:
> >
> > * No changes.
> >
> > v2 -> v3:
> >
> > * Add Masahiro's ack.
> >
> > v1 -> v2:
> >
> > * No changes.
> >
> > Sami, please scream if you are unhappy with how I worded this commit.
> >
> >  init/Kconfig | 3 +++
> >  1 file changed, 3 insertions(+)
> >
> > diff --git a/init/Kconfig b/init/Kconfig
> > index 9e22ee8fbd75e..c15ee42b82726 100644
> > --- a/init/Kconfig
> > +++ b/init/Kconfig
> > @@ -23,6 +23,9 @@ config LD_VERSION
> >  config CC_IS_CLANG
> >         def_bool $(success,$(CC) --version | head -n 1 | grep -q clang)
> >
> > +config LD_IS_LLD
> > +       def_bool $(success,$(LD) -v | head -n 1 | grep -q LLD)
> > +
> >  config CLANG_VERSION
> >         int
> >         default $(shell,$(srctree)/scripts/clang-version.sh $(CC))
> >
> > base-commit: 96c9a7802af7d500a582d89a8b864584fe878c1b
> > --
> > 2.26.2
> >