From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm1-f66.google.com ([209.85.128.66]:35335 "EHLO mail-wm1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730384AbfGPRGL (ORCPT ); Tue, 16 Jul 2019 13:06:11 -0400 Date: Tue, 16 Jul 2019 10:06:06 -0700 From: Nathan Chancellor Subject: Re: kbuild: Fail if gold linker is detected Message-ID: <20190716170606.GA38406@archlinux-threadripper> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-kbuild-owner@vger.kernel.org List-ID: To: Thomas Gleixner Cc: LKML , Linus Torvalds , x86@kernel.org, "H.J. Lu" , Masahiro Yamada , linux-kbuild@vger.kernel.org On Tue, Jul 16, 2019 at 02:47:56PM +0200, Thomas Gleixner wrote: > The gold linker has known issues of failing the build in random and > predictible ways. H.J. stated: > > "Since building a workable kernel for different kernel configurations > isn't a requirement for gold, I don't recommend gold for kernel." > > So instead of dealing with attempts to duct tape gold support without > understanding the root cause, fail the build when gold is detected. > > Signed-off-by: Thomas Gleixner > Link: https://lore.kernel.org/r/CAMe9rOqMqkQ0LNpm25yE_Yt0FKp05WmHOrwc0aRDb53miFKM+w@mail.gmail.com > --- > scripts/Kconfig.include | 3 +++ > 1 file changed, 3 insertions(+) > > --- a/scripts/Kconfig.include > +++ b/scripts/Kconfig.include > @@ -35,5 +35,8 @@ ld-option = $(success,$(LD) -v $(1)) > $(error-if,$(failure,command -v $(CC)),compiler '$(CC)' not found) > $(error-if,$(failure,command -v $(LD)),linker '$(LD)' not found) > > +# Fail if the linker is gold as it's not capable of linking the kernel proper > +$(error-if,$(success, command -v $(LD) -v | grep -q gold), gold linker '$(LD)' not supported) Why are there two '-v' flags here? The second one is ignored since command -v just prints out the path of the binary that is being used, which would work in most cases but not if gold is the default system linker. $ command -v ld.gold -v /usr/bin/ld.gold $ command -v ld.gold /usr/bin/ld.gold $ command ld.gold -v GNU gold (GNU Binutils 2.32) 1.16 Thus, wouldn't it be better to just call $(LD) directly, like CC_IS_GCC and CC_IS_CLANG in init/Kconfig? $(success, $(LD) -v | grep -q gold) Cheers, Nathan