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author | Wang Nan <wangnan0@huawei.com> | 2016-11-26 08:03:31 +0100 |
---|---|---|
committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2016-12-05 19:51:42 +0100 |
commit | cb40d55b595cd117ef7c1880247605875b2115e8 (patch) | |
tree | d5ba1a94d6f7d451f95e70feb17b93a7d5da65b0 /tools/build/feature | |
parent | perf llvm: Extract helpers in llvm-utils.c (diff) | |
download | linux-cb40d55b595cd117ef7c1880247605875b2115e8.tar.xz linux-cb40d55b595cd117ef7c1880247605875b2115e8.zip |
tools build: Add feature detection for LLVM
Check if basic LLVM compiling environment is ready.
Use llvm-config to detect include and library directories. Avoid using
'llvm-config --cxxflags' because its result contain some unwanted flags
like --sysroot (if LLVM is built by yocto).
Use '?=' to set LLVM_CONFIG, so explicitly passing LLVM_CONFIG to make
would override it.
Use 'llvm-config --libs BPF' to check if BPF backend is compiled in.
Since now BPF bytecode is the only required backend, no need to waste
time linking llvm and clang if BPF backend is missing. This also
introduce an implicit requirement that LLVM should be new enough. Old
LLVM doesn't support BPF backend.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Joe Stringer <joe@ovn.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/20161126070354.141764-8-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/build/feature')
-rw-r--r-- | tools/build/feature/Makefile | 8 | ||||
-rw-r--r-- | tools/build/feature/test-llvm.cpp | 8 |
2 files changed, 16 insertions, 0 deletions
diff --git a/tools/build/feature/Makefile b/tools/build/feature/Makefile index 8f668bce8996..c09de59affc9 100644 --- a/tools/build/feature/Makefile +++ b/tools/build/feature/Makefile @@ -55,6 +55,7 @@ FILES := $(addprefix $(OUTPUT),$(FILES)) CC := $(CROSS_COMPILE)gcc -MD CXX := $(CROSS_COMPILE)g++ -MD PKG_CONFIG := $(CROSS_COMPILE)pkg-config +LLVM_CONFIG ?= llvm-config all: $(FILES) @@ -229,6 +230,13 @@ $(OUTPUT)test-cxx.bin: $(OUTPUT)test-jvmti.bin: $(BUILD) +$(OUTPUT)test-llvm.bin: + $(BUILDXX) -std=gnu++11 \ + -I$(shell $(LLVM_CONFIG) --includedir) \ + -L$(shell $(LLVM_CONFIG) --libdir) \ + $(shell $(LLVM_CONFIG) --libs Core BPF) \ + $(shell $(LLVM_CONFIG) --system-libs) + -include $(OUTPUT)*.d ############################### diff --git a/tools/build/feature/test-llvm.cpp b/tools/build/feature/test-llvm.cpp new file mode 100644 index 000000000000..d8d2cee35345 --- /dev/null +++ b/tools/build/feature/test-llvm.cpp @@ -0,0 +1,8 @@ +#include "llvm/Support/ManagedStatic.h" +#include "llvm/Support/raw_ostream.h" +int main() +{ + llvm::errs() << "Hello World!\n"; + llvm::llvm_shutdown(); + return 0; +} |