1709987 - Assertion when shutting down ApplicationAccessible

Status: RESOLVED FIXED

(Core :: Disability Access APIs, defect, P1)

Description

[James Teh [:Jamie]]

After bug 1694865, I get this debug assertion when I exit Firefox with NVDA running:

Assertion failure: !mAcc (MsaaShutdown wasn't called!), at c:/Users/jamie/src/gecko2/accessible/windows/msaa/MsaaAccessible.cpp:76
#01: mozilla::a11y::MsaaAccessible::~MsaaAccessible (c:\Users\jamie\src\gecko2\accessible\windows\msaa\MsaaAccessible.cpp:76)
#02: mozilla::a11y::ia2AccessibleApplication::`vector deleting destructor'[C:\Users\jamie\src\gecko2\obj\dist\bin\xul.dll +0x5bb33a1]
#03: mozilla::a11y::ia2AccessibleApplication::Release[C:\Users\jamie\src\gecko2\obj\dist\bin\xul.dll +0x5bb334d]
#04: mozilla::a11y::ApplicationAccessibleWrap::~ApplicationAccessibleWrap (c:\Users\jamie\src\gecko2\accessible\windows\msaa\ApplicationAccessibleWrap.h:17)
#05: SnowWhiteKiller::MaybeKillObject (c:\Users\jamie\src\gecko2\xpcom\base\nsCycleCollector.cpp:2428)
#06: SnowWhiteKiller::~SnowWhiteKiller (c:\Users\jamie\src\gecko2\xpcom\base\nsCycleCollector.cpp:2411)
#07: nsCycleCollector::FreeSnowWhite (c:\Users\jamie\src\gecko2\xpcom\base\nsCycleCollector.cpp:2600)
#08: nsCycleCollector::Shutdown (c:\Users\jamie\src\gecko2\xpcom\base\nsCycleCollector.cpp:3643)
#09: nsCycleCollector_shutdown (c:\Users\jamie\src\gecko2\xpcom\base\nsCycleCollector.cpp:3960)
#10: mozilla::ShutdownXPCOM (c:\Users\jamie\src\gecko2\xpcom\build\XPCOMInit.cpp:711)
#11: ScopedXPCOMStartup::~ScopedXPCOMStartup (c:\Users\jamie\src\gecko2\toolkit\xre\nsAppRunner.cpp:1675)
#12: XREMain::XRE_main (c:\Users\jamie\src\gecko2\toolkit\xre\nsAppRunner.cpp:5582)

The reason is that ApplicationAccessible::Shutdown doesn't call AccessibleWrap::Shutdown, which means MsaaShutdown is never called.

Comment 1

[James Teh [:Jamie]]

Attachment: Bug 1709987: Call MsaaShutdown() when shutting down the ApplicationAccessible.

Comment 2

[James Teh [:Jamie]]

For the record, I think the reason this doesn't show up in tests is that it can only happen if a MsaaAccessible was created for the ApplicationAccessible. If a client doesn't make a Windows COM call to fetch the ApplicationAccessible (our tests can't and don't), there won't be an MsaaAccessible for it, and thus the assertion will never be reached.

Comment 3

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

Set release status flags based on info from the regressing bug 1694865

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/007b34eee7c9
Call MsaaShutdown() when shutting down the ApplicationAccessible. r=morgan

Comment 5

[Iulian Moraru]

https://hg.mozilla.org/mozilla-central/rev/007b34eee7c9