787675 - Trigger jemalloc release assertions from within a new stack frame

Status: RESOLVED FIXED

(Core :: Memory Allocator, defect)

Description

[Justin Lebar (not reading bugmail)]

Right now, jemalloc assertions are hard to decipher in crashstats.  A failed assertion crashes within the stack frame which invokes ASSERT, and presumably because of compiler optimizations, our crashstats often are not able to tell us exactly which assert failed.

Anyway, I think we can fix this by crashing within a new stack frame.  Patch in a moment.

Comment 1

[Justin Lebar (not reading bugmail)]

Attachment: Patch, v1

Comment 2

[Mike Hommey [:glandium]]

Comment on attachment 657570 [details] [diff] [review]
Patch, v1

Review of attachment 657570 [details] [diff] [review]:
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I think this should be done for MOZ_CRASH in a more general way, but that's ok to do it here for now (a related bug is bug 697301).

Comment 3

[Justin Lebar (not reading bugmail)]

> I think this should be done for MOZ_CRASH in a more general way

Hm, yeah, I agree.  Although I wonder if there are cases where MOZ_CRASH is used and they don't want an extra stack frame (e.g. because that might overflow the stack)?

Comment 4

[Justin Lebar (not reading bugmail)]

I filed bug 788069 on the general MOZ_CRASH case, although it's more complicated than I expected...

Comment 5

[Justin Lebar (not reading bugmail)]

https://hg.mozilla.org/integration/mozilla-inbound/rev/d155eefe75f3

Comment 6

[Ed Morley [:emorley]]

https://hg.mozilla.org/mozilla-central/rev/d155eefe75f3