C++: Add testcase with looping behavior in C/C++ use-use flow.

Author: MathiasVP

cpp/ql/test/library-tests/dataflow/dataflow-tests/dataflow-consistency.expected

@@ -92,6 +92,9 @@ postWithInFlow
 | test.cpp:499:3:499:4 | * ... [post update] | PostUpdateNode should not be the target of local flow. |
 | test.cpp:499:4:499:4 | p [inner post update] | PostUpdateNode should not be the target of local flow. |
 | test.cpp:505:35:505:35 | x [inner post update] | PostUpdateNode should not be the target of local flow. |
+| test.cpp:511:5:511:6 | * ... [post update] | PostUpdateNode should not be the target of local flow. |
+| test.cpp:511:6:511:6 | p [inner post update] | PostUpdateNode should not be the target of local flow. |
+| test.cpp:516:23:516:23 | x [inner post update] | PostUpdateNode should not be the target of local flow. |
 viableImplInCallContextTooLarge
 uniqueParameterNodeAtPosition
 uniqueParameterNodePosition

cpp/ql/test/library-tests/dataflow/dataflow-tests/dataflow-ir-consistency.expected

@@ -591,6 +591,12 @@ postWithInFlow
 | test.cpp:505:34:505:35 | & ... [post update] | PostUpdateNode should not be the target of local flow. |
 | test.cpp:505:34:505:35 | & ... [post update] | PostUpdateNode should not be the target of local flow. |
 | test.cpp:505:35:505:35 | x [post update] | PostUpdateNode should not be the target of local flow. |
+| test.cpp:511:5:511:6 | * ... [post update] | PostUpdateNode should not be the target of local flow. |
+| test.cpp:511:6:511:6 | VariableAddress [post update] | PostUpdateNode should not be the target of local flow. |
+| test.cpp:511:6:511:6 | p [post update] | PostUpdateNode should not be the target of local flow. |
+| test.cpp:516:22:516:23 | & ... [post update] | PostUpdateNode should not be the target of local flow. |
+| test.cpp:516:22:516:23 | & ... [post update] | PostUpdateNode should not be the target of local flow. |
+| test.cpp:516:23:516:23 | x [post update] | PostUpdateNode should not be the target of local flow. |
 | true_upon_entry.cpp:9:7:9:7 | VariableAddress [post update] | PostUpdateNode should not be the target of local flow. |
 | true_upon_entry.cpp:10:12:10:12 | VariableAddress [post update] | PostUpdateNode should not be the target of local flow. |
 | true_upon_entry.cpp:10:27:10:27 | VariableAddress [post update] | PostUpdateNode should not be the target of local flow. |

cpp/ql/test/library-tests/dataflow/dataflow-tests/test.cpp

@@ -505,3 +505,13 @@ void viaOutparamMissingReturn() {
   intOutparamSourceMissingReturn(&x);
   sink(x); // $ ast,ir
 }
+
+void sink_then_source(int* p) {
+    sink(*p);
+    *p = source(); // clean
+}
+
+void test_sink_then_source() {
+    int x;
+    sink_then_source(&x);
+}

cpp/ql/test/library-tests/dataflow/dataflow-tests/uninitialized.expected

@@ -34,3 +34,4 @@
 | test.cpp:441:7:441:11 | local | test.cpp:442:18:442:22 | local |
 | test.cpp:441:7:441:11 | local | test.cpp:443:8:443:12 | local |
 | test.cpp:441:7:441:11 | local | test.cpp:444:9:444:13 | local |
+| test.cpp:515:9:515:9 | x | test.cpp:516:23:516:23 | x |