t4018: test cases showing that the cpp pattern misses many anchor points

Most of the tests show C++ code, but there is also a union definition and
a GNU style function definition that are not recognized.

Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/t/t4018/cpp-function-returning-reference b/t/t4018/cpp-function-returning-reference
new file mode 100644
index 0000000..29e2bd4
--- /dev/null
+++ b/t/t4018/cpp-function-returning-reference
@@ -0,0 +1,5 @@
+string& get::it::RIGHT(char *ptr)
+{
+	ChangeMe;
+	broken;
+}