1059020 - "ASSERTION: bad size recorded" with accessibility, Notification

Status: RESOLVED FIXED

(Core :: Disability Access APIs, defect)

Description

[Jesse Ruderman]

Attachment: testcase

1. Run a debug build of Firefox with XPCOM_MEM_LEAK_LOG=2
     (to enable trace-refcnt code)

2. Set:
     user_pref("devtools.chrome.enabled", true);
 
3. Enable accessibility by pasting the following into the Browser Console:

Components.classes["@mozilla.org/accessibilityService;1"].getService(Components.interfaces.nsIAccessibleRetrieval);

4. Load the testcase.

Comment 1

[Jesse Ruderman]

Attachment: stack+

###!!! ASSERTION: bad size recorded: 'aInstanceSize == 0 || entry->GetClassSize() == aInstanceSize', file xpcom/base/nsTraceRefcnt.cpp, line 549

Comment 2

[Jesse Ruderman]

Attachment: the other stack

(sometimes I get one, sometimes I get the other?)

Comment 3

[Jesse Ruderman]

Like in bug 998706, the problem is two classes reporting the same name to trace-refcnt:

* mozilla::dom::Notification   (since 2014: bug 899585)
* mozilla::a11y::Notification  (since 2011: bug 498015)

Comment 4

[Jesse Ruderman]

Attachment: patch

Seems easier to change the a11y side, mostly because I have no idea what I'm doing.

This compiles and makes the assertion go away for me.

Comment 5

[alexander :surkov (:asurkov)]

Comment on attachment 8479506 [details] [diff] [review]
patch

Review of attachment 8479506 [details] [diff] [review]:
-----------------------------------------------------------------

::: accessible/base/NotificationController.h
@@ +25,5 @@
>   */
>  class Notification
>  {
>  public:
> +  NS_INLINE_DECL_REFCOUNTING(mozilla::a11y::Notification)

interesting, not sure how it can be resolved to dom::Notification.
perhaps shorter version a11y::Notification works too

Comment 6

[alexander :surkov (:asurkov)]

cc'ing Neil, it might be he has some explanation

Comment 7

[Trevor Saunders (:tbsaunde)]

(In reply to alexander :surkov from comment #5)
> Comment on attachment 8479506 [details] [diff] [review]
> patch
> 
> Review of attachment 8479506 [details] [diff] [review]:
> -----------------------------------------------------------------
> 
> ::: accessible/base/NotificationController.h
> @@ +25,5 @@
> >   */
> >  class Notification
> >  {
> >  public:
> > +  NS_INLINE_DECL_REFCOUNTING(mozilla::a11y::Notification)
> 
> interesting, not sure how it can be resolved to dom::Notification.
> perhaps shorter version a11y::Notification works too

the macro argument is just stringified and then fed to the leak logging stuff, so if you want things to not conflict you need to pass different strings.

Comment 8

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/165007d06d73