In bug 1028588 we removed dangerous public destructors of XPCOM-refcounted classes outside of a finite whitelist, see HasDangerousPublicDestructor. Now we are going over the entries in this whitelist. One of them is: nsNativeModuleLoader

This is ugly. nsComponentManagerImpl has a field with type nsNativeModuleLoader (not a pointer). nsNativeModuleLoader implements refcounting by forwarding it to nsComponentManagerImpl::gComponentManager. The only thing that ever addrefs nsNativeModuleLoader as far as I can see is some runnable. The nsNativeModuleLoader field can't just be turned into a ref ptr as this causes a "cycle" because it just addrefs gComponentManager, unless we just manually clear the native module loader field at some point in shutdown. Maybe that's not so bad.

I kind of want to disaggregate nsNativeModuleLoader (there are only a handful of classes that use it), by making the runnable directly hold onto gComponentManager directly, but I'm nervous that it will make things too fragile.

It is only used as a field of gComponentManager, so the full nsISupports and COM treatment isn't needed.

try run: https://tbpl.mozilla.org/?tree=Try&rev=506fa16ce0bb

Comment on attachment 8463433 [details] [diff] [review] part 3 - nsNativeModuleLoader doesn't need to implement ModuleLoader. Review of attachment 8463433 [details] [diff] [review]: ----------------------------------------------------------------- ::: xpcom/components/nsNativeModuleLoader.cpp @@ +89,5 @@ > return NS_OK; > } > > + nsRefPtr<nsComponentManagerImpl> mManager; > + nsNativeModuleLoader* mLoader; Hooray for more explicit lifetime management. ::: xpcom/components/nsNativeModuleLoader.h @@ -11,3 @@ > #include "nsDataHashtable.h" > #include "nsHashKeys.h" > -#include "mozilla/Module.h" All these headers just to cargo-cult FileLocation and the nsISupports bits? Ugh.

> All these headers just to cargo-cult FileLocation and the nsISupports bits? Ugh. Yeah it is awesome. remote: https://hg.mozilla.org/integration/mozilla-inbound/rev/ccfca130bbe3 remote: https://hg.mozilla.org/integration/mozilla-inbound/rev/e814aa7bab58 remote: https://hg.mozilla.org/integration/mozilla-inbound/rev/b84ac541b00e

https://hg.mozilla.org/mozilla-central/rev/ccfca130bbe3 https://hg.mozilla.org/mozilla-central/rev/e814aa7bab58 https://hg.mozilla.org/mozilla-central/rev/b84ac541b00e