Re: [PATCH v3 0/9] perf build: Support building with Clang

Arnaldo Carvalho de Melo
2025-10-06T18:50:36Z

On Mon, Oct 06, 2025 at 05:21:22PM +0100, Leo Yan wrote:
> This series adds support for building perf with Clang, following the
> discussion in [1]. Because the Android NDK uses Clang by default,
> enabling Clang builds naturally covers Android as well.
>
> The series is organized as follows:
>
> - Patches 1~2: Fix two bugs found with Clang.
> - Patches 3~7: Correct CROSS_ARCH, Disable thread safety analysis for
> perl header, and dismiss Clang build warnings.
> - Patches 8~9: Enable Clang in the Makefile and update the
> documentation.
>
> Testing:
>
> Tested with linux-tools-container-builds [2], which based on Arnaldo's
> build test container but with several fixes for cross building with
> Clang:
>
> - All clang native builds on x86_64 have passed.
> - The cross builds for arm64/mips/mips64/mipsel/riscv64 have passed.
>
> Only a pity thing is I cannot build successfully with clang for
> ubuntu:20.04-x-powerpc64el (in below log, it only builds with GCC).
> The cross config does not work well on Ubuntu 20.04 due to failure
> "No gnu/libc-version.h found, please install glibc-dev[el]". I confirmed
> that powerpc64el cross build can make success on Ubuntu 24.04, the
> failure on Ubuntu 20.04 should not be caused by perf build.
>
> Subject: tools build test for http://localhost/perf/perf-6.17.0-rc6.tar.xz

I shed a tear ;-)

And thanks for fixing the ubuntu cross builds, I'll apply those patches
you made available thru github,

Thanks a lot!

- Arnaldo

> 1 201.44 alpine:3.16 : Ok gcc (Alpine 11.2.1_git20220219) 11.2.1 20220219 , Alpine clang version 13.0.1 flex 2.6.4
> 2 154.82 alpine:3.17 : Ok gcc (Alpine 12.2.1_git20220924-r4) 12.2.1 20220924 , Alpine clang version 15.0.7 flex 2.6.4
> 3 136.07 alpine:3.18 : Ok gcc (Alpine 12.2.1_git20220924-r10) 12.2.1 20220924 , Alpine clang version 16.0.6 flex 2.6.4
> 4 150.21 alpine:3.19 : Ok gcc (Alpine 13.2.1_git20231014) 13.2.1 20231014 , Alpine clang version 17.0.5 flex 2.6.4
> 5 143.50 alpine:3.20 : Ok gcc (Alpine 13.2.1_git20240309) 13.2.1 20240309 , Alpine clang version 17.0.6 flex 2.6.4
> 6 146.08 amazonlinux:2023 : Ok gcc (GCC) 11.5.0 20240719 (Red Hat 11.5.0-5) , clang version 15.0.7 (AWS 15.0.7-3.amzn2023.0.4) flex 2.6.4
> 7 147.19 amazonlinux:devel : Ok gcc (GCC) 11.3.1 20221121 (Red Hat 11.3.1-4) , clang version 15.0.6 (Amazon Linux 15.0.6-3.amzn2023.0.2) flex 2.6.4
> 8 117.92 debian:11 : Ok gcc (Debian 10.2.1-6) 10.2.1 20210110 , Debian clang version 13.0.1-6~deb11u1 flex 2.6.4
> 9 121.54 debian:12 : Ok gcc (Debian 12.2.0-14+deb12u1) 12.2.0 , Debian clang version 14.0.6 flex 2.6.4
> 10 128.64 debian:experimental : Ok gcc (Debian 15.2.0-4) 15.2.0 , Debian clang version 19.1.7 (7) flex 2.6.4
> 11 96.47 debian:experimental-x-arm64 : Ok aarch64-linux-gnu-gcc (Debian 15.2.0-4) 15.2.0 , Debian clang version 19.1.7 (7) flex 2.6.4
> 12 72.89 debian:experimental-x-mips : Ok mips-linux-gnu-gcc (Debian 14.2.0-13) 14.2.0 , Debian clang version 19.1.7 (7) flex 2.6.4
> 13 73.31 debian:experimental-x-mips64 : Ok mips64-linux-gnuabi64-gcc (Debian 14.2.0-13) 14.2.0 , Debian clang version 19.1.7 (7) flex 2.6.4
> 14 71.69 debian:experimental-x-mipsel : Ok mipsel-linux-gnu-gcc (Debian 14.2.0-13) 14.2.0 , Debian clang version 19.1.7 (7) flex 2.6.4
> 15 151.92 fedora:35 : Ok gcc (GCC) 11.3.1 20220421 (Red Hat 11.3.1-3) , clang version 13.0.1 (Fedora 13.0.1-1.fc35) flex 2.6.4
> 16 146.99 fedora:36 : Ok gcc (GCC) 12.2.1 20221121 (Red Hat 12.2.1-4) , clang version 14.0.5 (Fedora 14.0.5-2.fc36) flex 2.6.4
> 17 139.58 fedora:37 : Ok gcc (GCC) 12.3.1 20230508 (Red Hat 12.3.1-1) , clang version 15.0.7 (Fedora 15.0.7-2.fc37) flex 2.6.4
> 18 142.00 fedora:38 : Ok gcc (GCC) 13.2.1 20240316 (Red Hat 13.2.1-7) , clang version 16.0.6 (Fedora 16.0.6-4.fc38) flex 2.6.4
> 19 140.18 fedora:39 : Ok gcc (GCC) 13.3.1 20240913 (Red Hat 13.3.1-3) , clang version 17.0.6 (Fedora 17.0.6-2.fc39) flex 2.6.4
> 20 139.38 fedora:40 : Ok gcc (GCC) 14.2.1 20240912 (Red Hat 14.2.1-3) , clang version 18.1.8 (Fedora 18.1.8-2.fc40) flex 2.6.4
> 21 136.26 fedora:41 : Ok gcc (GCC) 14.3.1 20250808 (Red Hat 14.3.1-3) , clang version 19.1.7 (Fedora 19.1.7-5.fc41) flex 2.6.4
> 22 135.38 fedora:42 : Ok gcc (GCC) 15.2.1 20250808 (Red Hat 15.2.1-1) , clang version 20.1.8 (Fedora 20.1.8-4.fc42) flex 2.6.4
> 23 127.55 fedora:rawhide : Ok gcc (GCC) 15.2.1 20250924 (Red Hat 15.2.1-2) , clang version 21.1.2 (Fedora 21.1.2-1.fc44) flex 2.6.4
> 24 180.17 opensuse:15.4 : Ok gcc (SUSE Linux) 7.5.0 , clang version 15.0.7 flex 2.6.4
> 25 169.40 opensuse:15.5 : Ok gcc (SUSE Linux) 7.5.0 , clang version 15.0.7 flex 2.6.4
> 26 167.36 opensuse:15.6 : Ok gcc (SUSE Linux) 7.5.0 , clang version 17.0.6 flex 2.6.4
> 27 154.82 opensuse:tumbleweed : Ok gcc (SUSE Linux) 15.2.0 , clang version 21.1.2 flex 2.6.4
> 28 145.89 oraclelinux:8 : Ok gcc (GCC) 8.5.0 20210514 (Red Hat 8.5.0-28.0.1) , clang version 19.1.7 ( 19.1.7-2.module+el8.10.0+90583+7e562d96) flex 2.6.1
> 29 139.68 oraclelinux:9 : Ok gcc (GCC) 11.5.0 20240719 (Red Hat 11.5.0-5.0.1) , clang version 19.1.7 ( 19.1.7-2.el9) flex 2.6.4
> 30 40.17 ubuntu:20.04 : Ok gcc (Ubuntu 9.4.0-1ubuntu1~20.04.2) 9.4.0 flex 2.6.4
> 31 20.83 ubuntu:20.04-x-powerpc64el : Ok powerpc64le-linux-gnu-gcc (Ubuntu 10.5.0-1ubuntu1~20.04) 10.5.0 flex 2.6.4
> 32 127.75 ubuntu:22.04 : Ok gcc (Ubuntu 11.4.0-1ubuntu1~22.04.2) 11.4.0 , Ubuntu clang version 14.0.0-1ubuntu1.1 flex 2.6.4
> 33 92.25 ubuntu:22.04-x-riscv64 : Ok riscv64-linux-gnu-gcc (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0 , Ubuntu clang version 14.0.0-1ubuntu1.1 flex 2.6.4
> 34 126.64 ubuntu:24.04 : Ok gcc (Ubuntu 13.3.0-6ubuntu2~24.04) 13.3.0 , Ubuntu clang version 18.1.3 (1ubuntu1) flex 2.6.4
> 35 130.95 ubuntu:25.04 : Ok gcc (Ubuntu 14.2.0-19ubuntu2) 14.2.0 , Ubuntu clang version 20.1.2 (0ubuntu1) flex 2.6.4
>
> [1] https://lore.kernel.org/linux-perf-users/20240715143342.52236-1-leo.yan@arm.com/
> [2] https://github.com/Leo-Yan/linux-tools-container-builds/tree/fix-riscv64-cross-build
>
> ---
> Changes in v3:
> - Fixed build failure with musl lib.
> - Disabled thread safety analysis for perl head.
> - Link to v2: https://lore.kernel.org/r/20250930-perf_build_android_ndk-v2-0-2ea440b7ef01@arm.com
>
> Changes in v2:
> - Dropped the patch for dismissing warning in bpftool.
> - Refined the document. (Ian)
> - Link to v1: https://lore.kernel.org/r/20250925-perf_build_android_ndk-v1-0-8b35aadde3dc@arm.com
>
> ---
> Leo Yan (9):
> tools build: Align warning options with perf
> perf python: split Clang options when invoking Popen
> perf build: Correct CROSS_ARCH for clang
> perf build: Disable thread safety analysis for perl header
> perf test coresight: Dismiss clang warning for memcpy thread
> perf test coresight: Dismiss clang warning for thread loop
> perf test coresight: Dismiss clang warning for unroll loop thread
> perf build: Support build with clang
> perf docs: Document building with Clang
>
> tools/build/feature/Makefile | 6 +-
> tools/perf/Documentation/Build.txt | 15 ++++
> tools/perf/Documentation/android.txt | 80 ++--------------------
> tools/perf/Makefile.config | 33 ++++++++-
> tools/perf/Makefile.perf | 2 +-
> tools/perf/scripts/perl/Perf-Trace-Util/Build | 2 +-
> .../shell/coresight/memcpy_thread/memcpy_thread.c | 2 +
> .../shell/coresight/thread_loop/thread_loop.c | 4 +-
> .../unroll_loop_thread/unroll_loop_thread.c | 4 +-
> tools/perf/util/scripting-engines/Build | 2 +-
> tools/perf/util/setup.py | 5 +-
> 11 files changed, 70 insertions(+), 85 deletions(-)
> ---
> base-commit: c17dda8013495d8132c976cbf349be9949d0fbd1
> change-id: 20250915-perf_build_android_ndk-500b53bea895
>
> Best regards,
> --
> Leo Yan <leo.yan@arm.com>