1260709 - Invalid source file in backtrace with Mac OS X

Status: RESOLVED INCOMPLETE

(Socorro :: General, task)

Description

[Calixte Denizet (:calixte)]

For the signature mozilla::dom::ConvertJSValueToString<T>, the backtrace for mac OS X is:
mozilla::dom::ConvertJSValueToString<mozilla::dom::binding_detail::FakeString> 	 js/src/jsfriendapi.h

and for Windows:
mozilla::dom::ConvertJSValueToString<mozilla::dom::binding_detail::FakeString> 	 dom/bindings/BindingUtils.h

The second seems to be correct.

Comment 1

[Sylvestre Ledru [:Sylvestre]]

Ted, do you think it is caused by breakpad?

Comment 2

[(not currently active) Ted Mielczarek]

This is just due to differences in how inlined functions show up in the debug info (as interpreted by Breakpad) between compilers.

For a Windows crash (https://crash-stats.mozilla.com/report/index/7b62b4dd-88be-4d57-b9fd-527042160327), frame 0 links to:
https://hg.mozilla.org/mozilla-central/annotate/8a4359ad909f/dom/bindings/BindingUtils.h#l2035 , but that line is actually a call to `AssignJSString`, so the crash actually occurred in there somewhere.

For a Mac OS X crash (https://crash-stats.mozilla.com/report/index/95b060de-24d3-4980-8d8b-8c4f32160327), frame 0 links to:
https://hg.mozilla.org/mozilla-central/annotate/8a4359ad909f/js/src/jsfriendapi.h#l907 , which is likely to be the actual crashing line.

`AssignJSString` is marked `inline`:
https://hg.mozilla.org/mozilla-central/annotate/8a4359ad909f/dom/base/nsJSUtils.h#l151

and it calls `js::CopyStringChars`, which is also marked `inline`:
https://hg.mozilla.org/mozilla-central/annotate/8a4359ad909f/js/src/jsfriendapi.h#l914

...and that calls `CopyLinearStringChars`, which is marked `MOZ_ALWAYS_INLINE`:
https://hg.mozilla.org/mozilla-central/annotate/8a4359ad909f/js/src/jsfriendapi.h#l900

Comment 3

[(not currently active) Ted Mielczarek]

I ran my get-minidump-instructions tool on both of the dumps from comment 2 (http://hg.mozilla.org/users/tmielczarek_mozilla.com/get-minidump-instructions/, bug 977778 is filed on making this accessible from the crash-stats UI), so you can see what the generated code + source info looks like around the crashing instruction.

Comment 4

[(not currently active) Ted Mielczarek]

Attachment: Windows crash 7b62b4dd-88be-4d57-b9fd-527042160327 disassembly

Comment 5

[(not currently active) Ted Mielczarek]

Attachment: Mac crash 95b060de-24d3-4980-8d8b-8c4f32160327 disassembly

Comment 6

[Will Kahn-Greene [:willkg] ET needinfo? me]

All of this has expired from the system. I don't see anything actionable here other than "work on bug #977778".

Closing this out as incomplete.