From b1ef2559d5579b1bc34f062aef53e9c1e52c91b0 Mon Sep 17 00:00:00 2001
From: Arnaldo Carvalho de Melo <acme@redhat.com>
Date: Wed, 11 Dec 2024 16:51:08 -0300
Subject: [PATCH] tools build feature: Don't set feature-libcap=1 if
 libcap-devel isn't available
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libcap isn't tested in the tools/build/feature/test-all.c fast path
feature detection process, so don't set it as available if test-all
manages to build.

There are other users of this feature detection mechanism, and they
explicitely ask for libcap to be tested, so are not affected by this
patch, for instance, with this patch in place:

  $ make -C tools/bpf/bpftool/ clean
  <SNIP>
  make: Leaving directory '/home/acme/git/perf-tools-next/tools/bpf/bpftool'
  ⬢ [acme@toolbox perf-tools-next]$ make -C tools/bpf/bpftool/
  make: Entering directory '/home/acme/git/perf-tools-next/tools/bpf/bpftool'

  Auto-detecting system features:
  ...                         clang-bpf-co-re: [ on  ]
  ...                                    llvm: [ on  ]
  ...                                  libcap: [ on  ]
  ...                                  libbfd: [ on  ]
  ...                             libelf-zstd: [ on  ]
  <SNIP>
    LINK    bpftool
  make: Leaving directory '/home/acme/git/perf-tools-next/tools/bpf/bpftool'
  $
  $ sudo rpm -e libcap-devel
  $ make -C tools/bpf/bpftool/
  <SNIP>
  make: Entering directory '/home/acme/git/perf-tools-next/tools/bpf/bpftool'

  Auto-detecting system features:
  ...                         clang-bpf-co-re: [ on  ]
  ...                                    llvm: [ on  ]
  ...                                  libcap: [ OFF ]
  ...                                  libbfd: [ on  ]
  ...                             libelf-zstd: [ on  ]

  $

Reviewed-by: Ian Rogers <irogers@google.com>
Acked-by: Quentin Monnet <qmo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/lkml/20241211224509.797827-3-acme@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/build/Makefile.feature | 2 --
 tools/build/feature/Makefile | 2 +-
 2 files changed, 1 insertion(+), 3 deletions(-)

diff --git a/tools/build/Makefile.feature b/tools/build/Makefile.feature
index 52600e4d33af..e25cdb7db40e 100644
--- a/tools/build/Makefile.feature
+++ b/tools/build/Makefile.feature
@@ -73,7 +73,6 @@ FEATURE_TESTS_BASIC :=                  \
         glibc                           \
         libbfd                          \
         libbfd-buildid			\
-        libcap                          \
         libelf                          \
         libelf-getphdrnum               \
         libelf-gelf_getnote             \
@@ -150,7 +149,6 @@ FEATURE_DISPLAY ?=              \
          glibc                  \
          libbfd                 \
          libbfd-buildid		\
-         libcap                 \
          libelf                 \
          libnuma                \
          numa_num_possible_cpus \
diff --git a/tools/build/feature/Makefile b/tools/build/feature/Makefile
index 043dfd00fce7..cbf751b6f0f7 100644
--- a/tools/build/feature/Makefile
+++ b/tools/build/feature/Makefile
@@ -110,7 +110,7 @@ all: $(FILES)
 __BUILD = $(CC) $(CFLAGS) -MD -Wall -Werror -o $@ $(patsubst %.bin,%.c,$(@F)) $(LDFLAGS)
   BUILD = $(__BUILD) > $(@:.bin=.make.output) 2>&1
   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) -DPACKAGE='"perf"' -lbfd -ldl -lz -llzma -lzstd -lcap
+  BUILD_ALL = $(BUILD) -fstack-protector-all -O2 -D_FORTIFY_SOURCE=2 -ldw -lelf -lnuma -lelf -lslang $(FLAGS_PERL_EMBED) $(FLAGS_PYTHON_EMBED) -DPACKAGE='"perf"' -lbfd -ldl -lz -llzma -lzstd
 
 __BUILDXX = $(CXX) $(CXXFLAGS) -MD -Wall -Werror -o $@ $(patsubst %.bin,%.cpp,$(@F)) $(LDFLAGS)
   BUILDXX = $(__BUILDXX) > $(@:.bin=.make.output) 2>&1
-- 
2.50.1