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

From: Arnaldo Carvalho de Melo
Date: Tue Sep 10 2024 - 10:38:29 EST


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@xxxxxxxxxx>
> ---
> 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]$