1126987 - TypeError: frame is null: MarkerDetails.prototype.renderStackTrace

Status: RESOLVED FIXED

(DevTools :: Performance Tools (Profiler/Timeline), defect)

Description

[Victor Porof [:vporof][:vp]]

Seeing a lot of these.

STR: Record while cnn.com is loading. Then click on random markers until you get this error.

TypeError: frame is null: MarkerDetails.prototype.renderStackTrace@resource://gre/modules/commonjs/toolkit/loader.js -> resource:///modules/devtools/timeline/marker-details.js:182:11
MarkerDetails.prototype.render@resource://gre/modules/commonjs/toolkit/loader.js -> resource:///modules/devtools/timeline/marker-details.js:151:1
WaterfallView._onMarkerSelected@chrome://browser/content/devtools/performance/views/details-waterfall.js:121:1
EventEmitter_emit@resource://gre/modules/commonjs/toolkit/loader.js -> resource://gre/modules/devtools/event-emitter.js:137:11
Waterfall.prototype.selectRow@resource://gre/modules/commonjs/toolkit/loader.js -> resource:///modules/devtools/timeline/waterfall.js:367:7
Waterfall.prototype._buildMarker/container.onclick@resource://gre/modules/commonjs/toolkit/loader.js -> resource:///modules/devtools/timeline/waterfall.js:330:33

Comment 1

[Tom Tromey :tromey]

stack.js initializes _lastEventSize to -1, then later in makeEvent does

    let packet = Array(size - this._lastEventSize).fill(null);

This results in a null entry in the frame array that is sent to the client.

The simplest fix is to initialize to zero. I have a patch that does this,
but I haven't written a test yet.

Comment 2

[Tom Tromey :tromey]

Attachment: fix _lastEventSize initialization in stack.js

Comment 3

[Tom Tromey :tromey]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=7d66285e5ca4

Comment 4

[Victor Porof [:vporof][:vp]]

Comment on attachment 8574816 [details] [diff] [review]
fix _lastEventSize initialization in stack.js

Review of attachment 8574816 [details] [diff] [review]:
-----------------------------------------------------------------

Only two big problems in computer science, right?

Comment 5

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/integration/fx-team/rev/94b360f64761

Comment 6

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/94b360f64761

Comment 7

[David Lawrence [:dkl]]

Sorry for the spam. Moving bugs to Firefox :: Developer Tools: Performance Tools (Profiler/Timeline).

dkl