878014 - WebAudio Assertion failure: readPosition >= 0.0 (Why are we reading before the beginning of the buffer?) [@mozilla::dom::DelayNodeEngine::ProduceAudioBlock]

Status: RESOLVED FIXED

(Core :: Web Audio, defect)

Description

[Christoph Diehl [:posidron]]

Attachment: testcase

The testcase will crash with an assertion failure in a debug build. In a non debug build, the testcase exposes the same crash as in bug 877523 for which a patch has been checked in with rev e12be295c0b1.

content/media/webaudio/DelayNode.cpp:215

    // Write the input sample to the correct location in our buffer
    if (input) {
*     buffer[writeIndex] = input[i] * aInput.mVolume;
    }


Tested with http://hg.mozilla.org/integration/mozilla-inbound/rev/db7a405f0a45

Comment 1

[Christoph Diehl [:posidron]]

Attachment: callstack

Comment 2

[(no longer active)]

(In reply to Christoph Diehl [:cdiehl] from comment #0)
> The testcase will crash with an assertion failure in a debug build. In a non
> debug build, the testcase exposes the same crash as in bug 877523 for which
> a patch has been checked in with rev e12be295c0b1.

Sure, this bug is very different than bug 877523.  And FWIW after I fix this there may still be more bugs in this code!  ;-)

Comment 3

[(no longer active)]

Attachment: Patch (v1)

Comment 4

[(no longer active)]

https://hg.mozilla.org/integration/mozilla-inbound/rev/9bcaba8046ee

Comment 5

[Phil Ringnalda (:philor)]

https://hg.mozilla.org/mozilla-central/rev/9bcaba8046ee

Comment 6

[(no longer active)]

Mass moving Web Audio bugs to the Web Audio component.  Filter on duckityduck.

Comment 7

[Ryan VanderMeulen [:RyanVM]]

Test disabled on B2G due to frequent timeouts.
https://hg.mozilla.org/integration/mozilla-inbound/rev/9df04b16a655