[PATCH v2 02/18] tools build: Integrate libdebuginfod into test-all fast path
From: Ian Rogers
Date: Tue May 12 2026 - 13:48:48 EST
Bundling libdebuginfod into test-all.c allows Make to avoid an individual
feature check sub-make fork during AST parsing. Short-circuit feature_check
in Makefile.feature to instantly skip sub-make evaluations when a feature
was already pre-detected by test-all.
Trade-offs:
On some Linux distributions (e.g., Debian/Ubuntu), libdebuginfod-dev is
packaged separately from libelf-dev and libdw-dev. If a user installs
libdw-dev but omits libdebuginfod-dev, adding -ldebuginfod to BUILD_ALL
causes test-all to fail, falling back to individual feature tests. However,
on fully configured developer workstations, this successfully reclaims
sequential startup latency.
Tested-by: James Clark <james.clark@xxxxxxxxxx>
Assisted-by: Gemini:gemini-3.1-pro-preview
Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
tools/build/Makefile.feature | 6 ++++--
tools/build/feature/Makefile | 2 +-
tools/build/feature/test-all.c | 5 +++++
3 files changed, 10 insertions(+), 3 deletions(-)
diff --git a/tools/build/Makefile.feature b/tools/build/Makefile.feature
index 2f192d3bf61b..d8febe5d5800 100644
--- a/tools/build/Makefile.feature
+++ b/tools/build/Makefile.feature
@@ -8,7 +8,9 @@ endif
feature_check = $(eval $(feature_check_code))
define feature_check_code
- feature-$(1) := $(shell $(MAKE) OUTPUT=$(OUTPUT_FEATURES) CC="$(CC)" CXX="$(CXX)" CFLAGS="$(EXTRA_CFLAGS) $(FEATURE_CHECK_CFLAGS-$(1))" CXXFLAGS="$(EXTRA_CXXFLAGS) $(FEATURE_CHECK_CXXFLAGS-$(1))" LDFLAGS="$(LDFLAGS) $(FEATURE_CHECK_LDFLAGS-$(1))" -C $(feature_dir) $(OUTPUT_FEATURES)test-$1.bin >/dev/null 2>/dev/null && echo 1 || echo 0)
+ ifeq ($(feature-$(1)),)
+ feature-$(1) := $(shell $(MAKE) OUTPUT=$(OUTPUT_FEATURES) CC="$(CC)" CXX="$(CXX)" CFLAGS="$(EXTRA_CFLAGS) $(FEATURE_CHECK_CFLAGS-$(1))" CXXFLAGS="$(EXTRA_CXXFLAGS) $(FEATURE_CHECK_CXXFLAGS-$(1))" LDFLAGS="$(LDFLAGS) $(FEATURE_CHECK_LDFLAGS-$(1))" -C $(feature_dir) $(OUTPUT_FEATURES)test-$1.bin >/dev/null 2>/dev/null && echo 1 || echo 0)
+ endif
endef
feature_set = $(eval $(feature_set_code))
@@ -100,6 +102,7 @@ FEATURE_TESTS_BASIC := \
disassembler-four-args \
disassembler-init-styled \
file-handle \
+ libdebuginfod \
libopenssl
# FEATURE_TESTS_BASIC + FEATURE_TESTS_EXTRA is the complete list
@@ -125,7 +128,6 @@ FEATURE_TESTS_EXTRA := \
clang \
libbpf \
libpfm4 \
- libdebuginfod \
clang-bpf-co-re \
bpftool-skeletons
diff --git a/tools/build/feature/Makefile b/tools/build/feature/Makefile
index 704c687ed3ad..dc828523b50a 100644
--- a/tools/build/feature/Makefile
+++ b/tools/build/feature/Makefile
@@ -115,7 +115,7 @@ __BUILD = $(CC) $(CFLAGS) -MD -Wall -Werror -o $@ $(patsubst %.bin,%.c,$(@F)) $(
BUILD_BFD = $(BUILD) -DPACKAGE='"perf"' -lbfd -ldl
BUILD_ALL = $(BUILD) -fstack-protector-all -O2 -D_FORTIFY_SOURCE=2 -ldw -lelf -lnuma -lelf -lslang \
$(FLAGS_PERL_EMBED) $(FLAGS_PYTHON_EMBED) -ldl -lz -llzma -lzstd \
- $(shell $(PKG_CONFIG) --libs --cflags openssl 2>/dev/null)
+ $(shell $(PKG_CONFIG) --libs --cflags openssl 2>/dev/null) -ldebuginfod
__BUILDXX = $(CXX) $(CXXFLAGS) -MD -Wall -Werror -o $@ $(patsubst %.bin,%.cpp,$(@F)) $(LDFLAGS)
BUILDXX = $(__BUILDXX) > $(@:.bin=.make.output) 2>&1
diff --git a/tools/build/feature/test-all.c b/tools/build/feature/test-all.c
index 1488bf6e6078..b6984236859f 100644
--- a/tools/build/feature/test-all.c
+++ b/tools/build/feature/test-all.c
@@ -146,6 +146,10 @@
# include "test-libopenssl.c"
#undef main
+#define main main_test_libdebuginfod
+# include "test-libdebuginfod.c"
+#undef main
+
int main(int argc, char *argv[])
{
main_test_libpython();
@@ -178,6 +182,7 @@ int main(int argc, char *argv[])
main_test_libzstd();
main_test_libtraceevent();
main_test_libopenssl();
+ main_test_libdebuginfod();
return 0;
}
--
2.54.0.563.g4f69b47b94-goog