344705 - nsIWidget::Destroy not called for XUL/WebShell windows

Status: NEW

(Core :: XUL, defect)

Description

[Mark Mentovai]

I noticed that nsIWidget::Destroy was not being called for my top-level windows.  nsXULWindow and nsWebShellWindow do not explicitly call Destroy(), but I think they should.  Does anyone disagree?  I propose placing a Destroy() call in nsWebShellWindow::Destroy() - I propose using this class instead of nsXULWindow because nsWebShellWindow is what actually creates the nsIWidget.

Comment 1

[Robert O'Callahan (:roc) (email my personal email if necessary)]

Don't we call Destroy() when we drop the last reference to the widget?

Comment 2

[Mark Mentovai]

We don't do that explicitly anywhere in xp code.  Some widget toolkits call Destroy() from destructors but we don't do this in either of the Mac toolkits.  We could do this as a sort of last-ditch thing, but it seems slightly abusive of the API to have Destroy() available but not use it.  I'm seeing Destroy() called for other widget instances, just not the one owned by nsWebShellWindow.

(I noticed this when tracking down a widget leak, I was expecting to see a call to Destroy() not matched by a destructor call, and to possibly use the location of the Destroy() call as a clue to find the leak.  Instead, I had to use good old-fashioned debugging technique.)

Comment 3

[BugBot [:suhaib / :marco/ :calixte]]

The bug assignee didn't login in Bugzilla in the last 7 months, so the assignee is being reset.