CPP: Fix issue when destructor body is missing.

Author: geoffw0

cpp/ql/src/jsf/4.10 Classes/AV Rule 79.ql

@@ -159,6 +159,14 @@ predicate unreleasedResource(Resource r, Expr acquire, File f, int acquireLine)
     )
     and f = acquire.getFile()
     and acquireLine = acquire.getLocation().getStartLine()
+
+    // check that any destructor for this class has a block; if it doesn't,
+    // we must be missing information.
+    and forall(Destructor d |
+      d = r.getDeclaringType().getAMember() and
+      not d.isCompilerGenerated() |
+      exists(d.getBlock())
+    ) 
 }
 
 predicate freedInSameMethod(Resource r, Expr acquire) {

cpp/ql/test/query-tests/jsf/4.10 Classes/AV Rule 79/AV Rule 79.expected

@@ -11,7 +11,6 @@
 | ExternalOwners.cpp:49:3:49:20 | ... = ... | Resource a is acquired by class MyScreen but not released anywhere in this class. |
 | ListDelete.cpp:21:3:21:21 | ... = ... | Resource first is acquired by class MyThingColection but not released anywhere in this class. |
 | NoDestructor.cpp:23:3:23:20 | ... = ... | Resource n is acquired by class MyClass5 but not released anywhere in this class. |
-| NoDestructor.cpp:75:3:75:21 | ... = ... | Resource ptr is acquired by class TemplateWithDestructor<int *> but not released anywhere in this class. |
 | PlacementNew.cpp:36:3:36:36 | ... = ... | Resource p1 is acquired by class MyTestForPlacementNew but not released anywhere in this class. |
 | SelfRegistering.cpp:25:3:25:24 | ... = ... | Resource side is acquired by class MyOwner but not released anywhere in this class. |
 | Variants.cpp:25:3:25:13 | ... = ... | Resource f is acquired by class MyClass4 but not released anywhere in this class. |

cpp/ql/test/query-tests/jsf/4.10 Classes/AV Rule 79/NoDestructor.cpp

@@ -72,7 +72,7 @@ class TemplateWithDestructor
 {
 public:
 	TemplateWithDestructor(int len) {
-		ptr = new char[len]; // GOOD [FALSE POSITIVE]
+		ptr = new char[len]; // GOOD
 	}
 
 	~TemplateWithDestructor()