[Buildroot] Status of LLVM

[Markus Mayer]

On Wed, 5 Aug 2020 at 08:31, Thomas Petazzoni
<thomas.petazzoni at bootlin.com> wrote:
>
> On Wed, 5 Aug 2020 16:36:12 +0200
> Romain Naour <romain.naour at gmail.com> wrote:
>
> > Last year I was able to build an aarch64 system with clang 8 (rootfs + kernel)
> > on a Potato Board.
> >
> > Recently I tried again with a riscv64 target running under qemu:
> >
> > https://asciinema.org/a/DDspJVktlVl1Rh97dwLgtYcRY
> >
> > Clang: 10.0
> > kernel: 5.7.12
> > Busybox: 1.31.1 + patch
> > gcc toolchain: Bootlin riscv64--glibc--bleeding-edge-2020.02-2.defconfig
> >
> > I need some time to continue to work on this series and convince upstream to add
> > cland support in Buildroot. But it means more maintenance work for Buildroot
> > maintainers/contributors to fix all packages that fail to build with clang.
> > At least, we need to enable autobuilders testing with clang if this support is
> > added.
>
> I think it makes sense to have support for clang in Buildroot, and we
> can certainly add testing for clang configurations in our autobuilders.
>
> The one thing that was still a bit unclear for me is whether it is
> possible to build a system with just clang, without a gcc compiler at
> all. Indeed, Buildroot isn't really suited/designed for building two
> different compilers/toolchains.

That is something I am also looking into. From what I have found so
far, it is possible to build binaries with clang without any reference
to GCC libraries and run-time when building natively. I am not yet
sure how to replicate this for cross-compilation or if it is possible
at all.

Regards,
-Markus


> Thomas
> --
> Thomas Petazzoni, CTO, Bootlin
> Embedded Linux and Kernel engineering
> https://bootlin.com