Closed Bug 1516679 Opened 5 years ago Closed 5 years ago

Damp custom.debugger test fails intermittently on Try on Win64 with same-compartment realms

Categories

(DevTools :: Debugger, defect)

defect
Not set
normal

Tracking

(Not tracked)

RESOLVED FIXED

People

(Reporter: jandem, Unassigned)

References

Details

With patches for bug 1514210 and dependent bugs damp times out intermittently on Try. Only on Win64 and I can't reproduce this locally.

I've been using printf debugging to narrow it down. I think it's a race condition, like this:

* We run the first of the 3 step tests [0]. 

* We call mapFrames from setSymbols. The "await updateFrameLocations" in mapFrames takes a long time to be resolved.

* In the meantime we start running the second step test.

* Now the mapFrames => MAP_FRAMES from setSymbols continues. This ends up incorrectly clearing the "selected frame" that was already set by the second step.

Basically it looks like the debugger is not fully paused between tests and things can race.

[0] https://searchfox.org/mozilla-central/rev/8a135a9c5a96b59269f544fcaee76d8fd5a7026a/testing/talos/talos/tests/devtools/addon/content/tests/debugger/custom.js#69-94
Jason, can you help me with this?

I've spent a lot of time debugging this on Try and I think this is about as far as I can get. I'm happy to send more patches to Try though - it reproes about 50% of the time on Win64 on Try so it's fairly reproducible.
Flags: needinfo?(jlaster)
I'd be happy to take a look. Are there some failing tests I can look at or a good way to reproduce it locally?
(In reply to Jason Laster [:jlast] from comment #2)
> I'd be happy to take a look. Are there some failing tests I can look at or a
> good way to reproduce it locally?

Unfortunately I was only able to reproduce this on Win64 on Try (Talos damp). However it looks like the problem disappeared after I rebased my patches! Maybe one of the recent debugger updates changed things enough to hide this, or something. 

I'll do some retriggers but hopefully they will be green and then I'm no longer blocked on this...
I believe this is fixed, feel free to re-open
Status: NEW → RESOLVED
Closed: 5 years ago
Flags: needinfo?(jlaster)
Resolution: --- → FIXED
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