[PATCH 1/2 Resend] perf build: Update feature check for clang and llvm

Thomas Richter
2023-07-25T15:05:21Z

Perf build auto-detects features and packages already installed
for its build. This is done in directory tools/build/feature. This
directory contains small sample programs. When they successfully
compile the necessary prereqs in form of libraries and header
files are present.

Such a check is also done for llvm and clang. And the checks fail.

Fix this and update to the latest C++ standard and use the
new library provided by clang (which contains new packaging)
see this link for reference:
https://fedoraproject.org/wiki/Changes/Stop-Shipping-Individual-Component-Libraries-In-clang-lib-Package

Output before:
# rm -f ./test-clang.bin; make test-clang.bin; ./test-clang.bin; \
ll test-clang.make.output
g++ -MD -Wall -Werror -o test-clang.bin test-clang.cpp \
> test-clang.make.output 2>&1 -std=gnu++14 \
-I/usr/include \
-L/usr/lib64 \
-Wl,--start-group -lclangBasic -lclangDriver \
-lclangFrontend -lclangEdit -lclangLex \
-lclangAST -Wl,--end-group \
-lLLVM-16 \
\
> test-clang.make.output 2>&1
make: *** [Makefile:356: test-clang.bin] Error 1
-bash: ./test-clang.bin: No such file or directory
-rw-r--r--. 1 root root 252041 Jul 12 09:56 test-clang.make.output
#

File test-clang.make.output contains many lines of unreferenced
symbols.

Output after:
# rm -f ./test-clang.bin; make test-clang.bin; ./test-clang.bin; \
cat test-clang.make.output
g++ -MD -Wall -Werror -o test-clang.bin test-clang.cpp \
> test-clang.make.output 2>&1 -std=gnu++17 \
-I/usr/include \
-L/usr/lib64 \
-Wl,--start-group -lclang-cpp -Wl,--end-group \
-lLLVM-16 \
\
> test-clang.make.output 2>&1
#

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
---
tools/build/feature/Makefile | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/tools/build/feature/Makefile b/tools/build/feature/Makefile
index 2cd6dbbee088..3184f387990a 100644
--- a/tools/build/feature/Makefile
+++ b/tools/build/feature/Makefile
@@ -340,7 +340,7 @@ $(OUTPUT)test-jvmti-cmlr.bin:
$(BUILD)

$(OUTPUT)test-llvm.bin:
- $(BUILDXX) -std=gnu++14 \
+ $(BUILDXX) -std=gnu++17 \
-I$(shell $(LLVM_CONFIG) --includedir) \
-L$(shell $(LLVM_CONFIG) --libdir) \
$(shell $(LLVM_CONFIG) --libs Core BPF) \
@@ -348,17 +348,15 @@ $(OUTPUT)test-llvm.bin:
> $(@:.bin=.make.output) 2>&1

$(OUTPUT)test-llvm-version.bin:
- $(BUILDXX) -std=gnu++14 \
+ $(BUILDXX) -std=gnu++17 \
-I$(shell $(LLVM_CONFIG) --includedir) \
> $(@:.bin=.make.output) 2>&1

$(OUTPUT)test-clang.bin:
- $(BUILDXX) -std=gnu++14 \
+ $(BUILDXX) -std=gnu++17 \
-I$(shell $(LLVM_CONFIG) --includedir) \
-L$(shell $(LLVM_CONFIG) --libdir) \
- -Wl,--start-group -lclangBasic -lclangDriver \
- -lclangFrontend -lclangEdit -lclangLex \
- -lclangAST -Wl,--end-group \
+ -Wl,--start-group -lclang-cpp -Wl,--end-group \
$(shell $(LLVM_CONFIG) --libs Core option) \
$(shell $(LLVM_CONFIG) --system-libs) \
> $(@:.bin=.make.output) 2>&1
--
2.41.0