From: Wang Nan <[email protected]> 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 <[email protected]> Cc: Alexei Starovoitov <[email protected]> Cc: He Kuang <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Joe Stringer <[email protected]> Cc: Zefan Li <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> --- tools/build/feature/Makefile | 8 ++++++++ tools/build/feature/test-llvm.cpp | 8 ++++++++ 2 files changed, 16 insertions(+) create mode 100644 tools/build/feature/test-llvm.cpp 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; +} -- 2.9.3
