XPCOMGC/GCObject Inheritance

We need to make sure that every object which is used as a COM object inherits only once from GCObject.

Part I: Figuring out which classes need GCObject love

Print a list "A" of all classes which meet the following conditions:

• The class inherits (directly or indirectly) from nsISupports
• The class constructor is called by a method that is not a subclass constructor, e.g.

class A : public nsIObserver
{
public:
  NS_DECL_ISUPPORTS
  NS_DECL_NSIOBSERVER
private:
  nsCOMPtr<nsIFoo> mFoo;
};

class B : public A
{
public:
  NS_DECL_NSIOBSERVER
};

class C : public nsIFoo
{
public:
  NS_DECL_NSIFOO
};

int main()
{
  B b(); // Flag class B but not class A
  C* c = new C(); // Flag class C
}

Part II: subtract subclasses of list A

For each class in list "A", look to see if it a subclass of another class in list A. If so, remove it from the list. This is list "B"

Part III: rewrite the classes of list B to inherit from GCFinalizedObject

For each class in list B, make the class a subclass of GCFinalizedObject.

Note: if we can complete steps I and II with dehydra and get the start position of the class declarations, it may be easier to do this with a text-processing program than with pork