preprocessor: add (failing) test for concatenation

Change-Id: I9d51798cb4d95141d30b0609d03cd1d199088f0a
Reviewed-by: hjk <qthjk@ovi.com>

tests/auto/cplusplus/preprocessor/data/poundpound.1.cpp

+struct QQ {};
+
+#define NN(x) typedef QQ PP ## x;
+
+NN(CC)
+
+typedef PPCC RR;

tests/auto/cplusplus/preprocessor/data/poundpound.1.out.cpp

+# 1 "data/poundpound.1.cpp"
+struct QQ {};
+#gen true
+# 3 "data/poundpound.1.cpp"
+typedef QQ PPCC;
+#gen false
+# 7 "data/poundpound.1.cpp"
+typedef PPCC RR;

tests/auto/cplusplus/preprocessor/tst_preprocessor.cpp

@@ -683,6 +683,8 @@ void tst_Preprocessor::comparisons_data()
         << "empty-macro.cpp" << "empty-macro.out.cpp" << "";
     QTest::newRow("empty-macro 2")
         << "empty-macro.2.cpp" << "empty-macro.2.out.cpp" << "";
+    QTest::newRow("poundpound 1")
+        << "poundpound.1.cpp" << "poundpound.1.out.cpp" << "";
 }
 
 void tst_Preprocessor::comparisons()