Re: [PATCH 1/2] perf build: Autodetect minimum required llvm-dev version

[Arnaldo Carvalho de Melo <acme@kernel.org>]

On Tue, Sep 10, 2024 at 03:04:00PM +0100, James Clark wrote:
> The new LLVM addr2line feature requires a minimum version of 13 to
> compile. Add a feature check for the version so that NO_LLVM=1 doesn't
> need to be explicitly added. Leave the existing llvm feature check
> intact because it's used by tools other than Perf.
> 
> This fixes the following compilation error when the llvm-dev version
> doesn't match:
> 
>   util/llvm-c-helpers.cpp: In function 'char* llvm_name_for_code(dso*, const char*, u64)':
>   util/llvm-c-helpers.cpp:178:21: error: 'std::remove_reference_t<llvm::DILineInfo>' {aka 'struct llvm::DILineInfo'} has no member named 'StartAddress'
>     178 |   addr, res_or_err->StartAddress ? *res_or_err->StartAddress : 0);
> 
> Fixes: c3f8644c21df ("perf report: Support LLVM for addr2line()")
> Signed-off-by: James Clark <james.clark@linaro.org>
> ---
>  tools/build/Makefile.feature           |  2 +-
>  tools/build/feature/Makefile           |  9 +++++++++
>  tools/build/feature/test-llvm-perf.cpp | 14 ++++++++++++++
>  tools/perf/Makefile.config             |  6 +++---
>  4 files changed, 27 insertions(+), 4 deletions(-)
>  create mode 100644 tools/build/feature/test-llvm-perf.cpp
> 
> diff --git a/tools/build/Makefile.feature b/tools/build/Makefile.feature
> index 0717e96d6a0e..427a9389e26c 100644
> --- a/tools/build/Makefile.feature
> +++ b/tools/build/Makefile.feature
> @@ -136,7 +136,7 @@ FEATURE_DISPLAY ?=              \
>           libunwind              \
>           libdw-dwarf-unwind     \
>           libcapstone            \
> -         llvm                   \
> +         llvm-perf              \
>           zlib                   \
>           lzma                   \
>           get_cpuid              \

There was one leftover on the other patch, I added it here:

⬢[acme@toolbox perf-tools-next]$ git diff
diff --git a/tools/build/Makefile.feature b/tools/build/Makefile.feature
index 427a9389e26cd203..ffd117135094cc68 100644
--- a/tools/build/Makefile.feature
+++ b/tools/build/Makefile.feature
@@ -100,7 +100,6 @@ FEATURE_TESTS_EXTRA :=                  \
          libunwind-debug-frame-aarch64  \
          cxx                            \
          llvm                           \
-         llvm-version                   \
          clang                          \
          libbpf                         \
          libbpf-btf__load_from_kernel_by_id \
⬢[acme@toolbox perf-tools-next]$