C++: Add FP test.

Author: MathiasVP

cpp/ql/test/query-tests/Security/CWE/CWE-416/semmle/tests/IteratorToExpiredContainer/IteratorToExpiredContainer.expected

@@ -4,3 +4,4 @@
 | test.cpp:702:27:702:27 | call to operator[] | This object is destroyed at the end of the full-expression. |
 | test.cpp:727:23:727:23 | call to operator[] | This object is destroyed at the end of the full-expression. |
 | test.cpp:735:23:735:23 | call to operator[] | This object is destroyed at the end of the full-expression. |
+| test.cpp:803:3:803:3 | pointer to ~vector output argument | This object is destroyed at the end of the full-expression. |

cpp/ql/test/query-tests/Security/CWE/CWE-416/semmle/tests/IteratorToExpiredContainer/test.cpp

@@ -792,4 +792,13 @@ void test4() {
   // function we may end up in the destructor call `chunk.~A()`in `A.foo`. This destructor
   // call can flow to `begin` through the back-edge and cause a strange FP.
   auto zero = A().size();
+}
+
+void test5(int i)
+{
+  while(i < 10) {
+    const auto& vvs = returnValue();
+    for(const auto& vs : vvs) { }
+    ++i;
+  } // GOOD [FALSE POSITIVE]
 }