402535 - Cycle collection crashes with Leak Monitor extension installed

Status: RESOLVED FIXED

(Core :: XPConnect, defect, P1)

Description

[Peter Van der Beken [:peterv]]

We're trying to trace a context without a global object. That context is created when the service something gets the service @dbaron.org/leak-monitor-service;1. The cycle collector should just deal.
This should be blocking M9, we want people to use that extension to help us track down leaks.

Comment 1

[Peter Van der Beken [:peterv]]

Attachment: v1

Comment 2

[Peter Van der Beken [:peterv]]

Attachment: v1 (diff -w)

This makes us not add contexts with null globalobjects to mClearedGlobalObjects so that when we look up global objects corresponding to contexts in TraceXPConnectRoots we only get a non-null globalobject if the context is in mClearedGlobalObjects.

Comment 3

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Anybody using cycle collector with trunk is overriding extension compatibility; it isn't even close to working for finding leaks anymore.

Comment 4

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Er, anybody using *leak monitor* with trunk since cycle collector landed is ...

Comment 5

[Peter Van der Beken [:peterv]]

This might be triggered by more than just Leak Monitor though. Also, wouldn't it make it harder to fix Leak Monitor so it works with the beta?

Comment 6

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

It might.  I'm just surprised people are using current leak monitor.

Comment 7

[Mike Beltzner [:beltzner, not reading bugmail]]

Blocking, but agree with dbaron and don't think it should hold up beta unless there's a solid expectation that this indicates another potential crash in the cycle collector: peterv, is that what you're saying?

Comment 8

[Mike Beltzner [:beltzner, not reading bugmail]]

s/Blocking/I think this should block final,/ above

Comment 9

[Damon Sicore (:damons)]

Yeah, discussed with peterv.  Marking as blocking.  Let's get this landed.  Also, sounds like we need to get leak monitor working in general.  Is there a bug for that?

Comment 10

[Peter Van der Beken [:peterv]]

I think this is showing up as js_GetGCThingFlags crashes on breakpad: http://crash-stats.mozilla.com/report/list?range_unit=weeks&query_search=signature&query_type=contains&signature=js_GetGCThingFlags&query=js_GetGCThingFlags&range_value=1

Comment 11

[Myk Melez [:myk] [@mykmelez]]

FWIW, I wasn't using Leak Monitor when I started experiencing this crash, but it was enabled, since I have compatibility checking turned off.  There may be other folks in the same boat who aren't actually using the extension but still have it enabled.