Re: [PATCH v4 0/4] tools/build: Allow versioning of all LLVM tools

[Kumar Kartikeya Dwivedi]

On Sat Jul 25, 2026 at 1:31 AM CEST, Namhyung Kim wrote:
> On Fri, Jul 24, 2026 at 07:19:45PM +0200, Kumar Kartikeya Dwivedi wrote:
>> On Thu Jul 16, 2026 at 1:46 AM CEST, Namhyung Kim wrote:
>> > Hello BPF folks,
>> >
>> > On Wed, Jul 15, 2026 at 03:53:47PM +0100, James Clark wrote:
>> >> I ran into the build issue mentioned in the first commit, because using
>> >> an option like LLVM=-15 is a documented way to build [1], but only
>> >> some of the LLVM tools defined in tools/ support this.
>> >>
>> >> After fixing that, a lot of other tidyups fell out. I didn't go too far,
>> >> for example some selftests include tools/testing/selftests/lib.mk which
>> >> reimplements some of the LLVM_SUFFIX stuff, but other selftests include
>> >> tools/scripts/Makefile.include and I stopped before touching the former.
>> >> Some other non build scripts hard code toolchains and I didn't touch
>> >> those either, this change is only focused on things that already
>> >> include Makefile.include.
>> >>
>> >> [1]: Documentation/kbuild/llvm.rst
>> >>
>> >> Signed-off-by: James Clark <james.clark@xxxxxxxxxx>
>> >> ---
>> >> Changes in v4:
>> >> - Drop "tools/build: selftests: Allow versioning LLVM lld", clang
>> >>   already picks the correct sibling lld version. (Sashiko)
>> >> - Link to v3: https://lore.kernel.org/r/20260715-james-perf-llvm-version-v3-0-8854bfe5af7e@xxxxxxxxxx
>> >>
>> >> Changes in v3:
>> >> - Add warning for empty $USE_LD
>> >> - Use $HOSTREADELF in bpf Makefile
>> >> - Rebase on v7.2-rc3
>> >> - Link to v2: https://lore.kernel.org/r/20260518-james-perf-llvm-version-v2-0-f12cc4f031d8@xxxxxxxxxx
>> >>
>> >> Changes in v2:
>> >> - Fix selftests/bpf build. LLD needs to take the full path to be used
>> >>   with -fuse-ld=
>> >> - Link to v1: https://lore.kernel.org/r/20260514-james-perf-llvm-version-v1-0-6cac1a9a4c8d@xxxxxxxxxx
>> >>
>> >> ---
>> >> James Clark (4):
>> >>       tools/build: Allow versioning of all LLVM tools defined in Makefile.include
>> >>       tools/build: Indent if else blocks
>> >>       tools/build: Allow versioning LLVM readelf
>> >>       tools/build: selftests: Remove some duplicate toolchain definitions
>> >>
>> >>  tools/bpf/resolve_btfids/Makefile    |  3 --
>> >>  tools/lib/api/Makefile               |  4 --
>> >>  tools/lib/bpf/Makefile               |  8 ++--
>> >>  tools/lib/subcmd/Makefile            |  4 --
>> >>  tools/lib/symbol/Makefile            |  4 --
>> >>  tools/perf/Makefile.perf             |  7 ----
>> >>  tools/scripts/Makefile.include       | 77 ++++++++++++++++++++----------------
>> >>  tools/testing/selftests/bpf/Makefile |  1 -
>> >>  8 files changed, 46 insertions(+), 62 deletions(-)
>> >
>> > Are you ok with this change and going through perf tree?
>> >
>>
>> Sorry for the delay, yes, feel free to take it through your tree.
>
> Thanks, can I take it as your Acked-by?
>

Sure.

Acked-by: Kumar Kartikeya Dwivedi <memxor@xxxxxxxxx>

> Namhyung