Re: [PATCH v2] kbuild: Fail if gold linker is detected

From: Nathan Chancellor
Date: Tue Jul 16 2019 - 16:00:04 EST

On Tue, Jul 16, 2019 at 09:47:27PM +0200, Thomas Gleixner wrote:
> The gold linker has known issues of failing the build both in random and in
> predictible ways:
> - The x86/X32 VDSO build fails with:
> arch/x86/entry/vdso/vclock_gettime-x32.o:vclock_gettime.c:function do_hres:
> error: relocation overflow: reference to 'hvclock_page'
> That's a known issue for years and the usual workaround is to disable
> CONFIG_X86_32
> - A recent build failure is caused by turning a relocation into an
> absolute one for unknown reasons. See link below.
> - There are a couple of gold workarounds applied already, but reports
> about broken builds with keep coming in on a regular base and in
> most cases the root cause is unclear.
> In context of the most recent fail 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 and without support from the gold folks, fail
> the build when gold is detected.
> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
> Link:

Based on the crude little testing script I wrote below:

Reviewed-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
Tested-by: Nathan Chancellor <natechancellor@xxxxxxxxx>

$ cat

# ld.bfd (expected to pass)
make distclean defconfig || exit ${?}

# explicitly (expected to fail)
make distclean defconfig && exit ${?}

# as if it were the system linker (expected to fail)
ln -fs /usr/bin/ ld
PATH=${PWD}:${PATH} make distclean defconfig && exit ${?}

# ld.lld (expected to pass)
make LD=ld.lld distclean defconfig || exit ${?}