806754 - "ASSERTION: Stream already destroyed"

Status: RESOLVED FIXED

(Core :: Audio/Video, defect)

Description

[Jesse Ruderman]

Attachment: testcase

1. Save the testcase.
2. Fix the path in the testcase so it points at frames.webm in your tree.
3. Load the testcase.
4. Wait until the video finishes (~5 seconds).

Result:

###!!! ASSERTION: Stream already destroyed: '!aMessage->GetStream() || !aMessage->GetStream()->IsDestroyed()', file content/media/MediaStreamGraph.cpp, line 1717

The testcase is a slight perturbation of http://mxr.mozilla.org/mozilla-central/source/layout/reftests/webm-video/bug686957.html?force=1

Comment 1

[Jesse Ruderman]

Attachment: stack

Comment 2

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

Attachment: Make MediaDecoders detect when a MediaStream has been destroyed because its DOM wrapper has been collected, and remove the no-longer-relevant MediaStream from the output list

Jesse, what's the state of the art in writing tests that require GCs at particular times? Can we do that reliably?

Comment 3

[Jesse Ruderman]

As part of the test suite?  Try SpecialPowers.gc() or SpecialPowers.forceGC().

http://hg.mozilla.org/mozilla-central/file/e9f39220b8e7/testing/specialpowers/content/specialpowersAPI.js#l937

Comment 4

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

(In reply to Jesse Ruderman from comment #3)
> As part of the test suite?  Try SpecialPowers.gc() or
> SpecialPowers.forceGC().

Does that actually reliably destroy unreachable wrapped DOM objects synchronously during the gc() call?

Comment 5

[Jesse Ruderman]

I don't know.  It's possible you'll need a CC too.  Play with it?

Comment 6

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

Attachment: Part 2: fix bogus assertions and add test

See comments in patch.

Comment 7

[Chris Pearce [:cpearce (Not reading bugmail)]]

Comment on attachment 707431 [details] [diff] [review]
Part 2: fix bogus assertions and add test

Review of attachment 707431 [details] [diff] [review]:
-----------------------------------------------------------------

::: content/media/test/test_streams_gc.html
@@ +26,5 @@
> +
> +  a.addEventListener("seeked", function() {
> +    a.play();
> +
> +	a.addEventListener("play", function() {

Mixing tabs and spaces here?

Comment 8

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

https://hg.mozilla.org/integration/mozilla-inbound/rev/62f4bc028c72
https://hg.mozilla.org/integration/mozilla-inbound/rev/d4a6570ca6b0

Comment 9

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/62f4bc028c72
https://hg.mozilla.org/mozilla-central/rev/d4a6570ca6b0