tools build: Add feature detection for g++

Check if g++ is available. The result will be used by builtin clang and
LLVM support. Since LLVM requires C++11, this feature detector checks
std::move().

Signed-off-by: Wang Nan <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: He Kuang <[email protected]>
Cc: Jiri Olsa <[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]>
diff --git a/tools/build/feature/test-cxx.cpp b/tools/build/feature/test-cxx.cpp
new file mode 100644
index 0000000..b1dee9a3
--- /dev/null
+++ b/tools/build/feature/test-cxx.cpp
@@ -0,0 +1,15 @@
+#include <iostream>
+#include <memory>
+
+static void print_str(std::string s)
+{
+	std::cout << s << std::endl;
+}
+
+int main()
+{
+	std::string s("Hello World!");
+	print_str(std::move(s));
+	std::cout << "|" << s << "|" << std::endl;
+	return 0;
+}