On Mon, 22 Nov 2021 at 19:23, Jean-Philippe Brucker
<jean-philippe@xxxxxxxxxx> wrote:
>
> Add support for cross-building BPF tools and selftests with clang, by
> passing LLVM=1 or CC=clang to make, as well as CROSS_COMPILE. A single
> clang toolchain can generate binaries for multiple architectures, so
> instead of having prefixes such as aarch64-linux-gnu-gcc, clang uses the
> -target parameter: `clang -target aarch64-linux-gnu'.
>
> Patch 1 adds the parameter in Makefile.include so tools can easily
> support this. Patch 2 prepares for the libbpf change from patch 3 (keep
> building resolve_btfids's libbpf in the host arch, when cross-building
> the kernel with clang). Patches 3-6 enable cross-building BPF tools with
> clang.
The set looks good to me. I checked that the tools are still building
(without cross-compiling). I currently have issues building the
selftests on my setup, but they don't appear to be related to this
patchset.
Acked-by: Quentin Monnet <quentin@xxxxxxxxxxxxx>
Note that on bpf-next, patch 5 (runqslower) has a conflict with
be79505caf3f ("tools/runqslower: Install libbpf headers when
building").
Did you consider enabling cross-compiling for the BPF samples too? I'm
asking because the build system is pretty similar to the BPF tools.
Thanks,
Quentin
