Merge pull request #672 from geoffw0/lgtm1605

CPP: Fix function pointer/lambda related false positives in 'Resource not released in destructor'

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

@@ -10,6 +10,7 @@
 | DeleteThis.cpp:60:3:60:24 | ... = ... | Resource ptr14 is acquired by class MyClass3 but not released anywhere in this class. |
 | DeleteThis.cpp:127:3:127:20 | ... = ... | Resource d is acquired by class MyClass9 but not released anywhere in this class. |
 | ExternalOwners.cpp:49:3:49:20 | ... = ... | Resource a is acquired by class MyScreen but not released anywhere in this class. |
+| Lambda.cpp:24:3:24:21 | ... = ... | Resource r4 is acquired by class testLambda 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. |
 | PlacementNew.cpp:36:3:36:36 | ... = ... | Resource p1 is acquired by class MyTestForPlacementNew but not released anywhere in this class. |

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

@@ -0,0 +1,56 @@
+
+class testLambda
+{
+public:
+	testLambda()
+	{
+		r1 = new char[4096]; // GOOD
+		deleter1 = [](char *r) {
+			delete [] r;
+		};
+
+		r2 = new char[4096]; // GOOD
+		auto deleter2 = [this]() {
+			delete [] r2;
+		};
+		deleter2();
+
+		r3 = new char[4096]; // GOOD
+		auto deleter3 = [&r = r3]() {
+			delete [] r;
+		};
+		deleter3(); 
+
+		r4 = new char[4096]; // BAD
+
+		r5 = new char[4096]; // GOOD
+		deleter5 = &deleter_for_r5;
+
+		r6 = new char[4096]; // GOOD
+		deleter6 = &testLambda::deleter_for_r6;
+	}
+
+	static void deleter_for_r5(char *r)
+	{
+		delete [] r;
+	}
+
+	void deleter_for_r6()
+	{
+		delete [] r6;
+	}
+
+	~testLambda()
+	{
+		deleter1(r1);
+		deleter5(r5);
+		((*this).*deleter6)();
+	}
+
+private:
+	char *r1, *r2, *r3, *r4, *r5, *r6;
+
+	void (*deleter1)(char *r);
+	void (*deleter5)(char *r);
+	void (testLambda::*deleter6)();
+};