1266333 - Functions missing argument lists in Breakpad symbol files

Status: NEW

(Toolkit :: Crash Reporting, defect)

Description

[Calixte Denizet (:calixte)]

In [1], each signature is given with function arguments and it isn't the case in [2].

[1] https://crash-stats.mozilla.com/report/index/d106780c-cc8c-4692-a8f4-973b92160419
[2] https://crash-stats.mozilla.com/report/index/cadb575f-7510-4710-9ff3-cd3652160416

Comment 1

[Calixte Denizet (:calixte)]

A grep on nsDragService::SetDragIcon shows that in [1] args are presents but not in [2].

[1] http://symbols.mozilla.org/libxul.so/065F2208BA0CD931ABEFDF81E99713230/libxul.so.sym
[2] http://symbols.mozilla.org/libxul.so/E17B1A543A454216CBFA732E1D2201B30/libxul.so.sym

Comment 2

[(not currently active) Ted Mielczarek]

Specifically, the grep output looks like:
```
/tmp/libxul.sym.1:FUNC 21b2614 1ca 0 nsDragService::SetDragIcon(_GdkDragContext*)
/tmp/libxul.sym.2:FUNC 1be6b20 1a7 0 nsDragService::SetDragIcon
```

The symbol files conveniently have the changeset information in them, so the regression range here is:
https://hg.mozilla.org/integration/mozilla-inbound/pushloghtml?fromchange=946ed22cad04431c75ab5093989dfedf1bae5a3e&tochange=afd82f887093

That's a lot of changes, so I built a Mercurial query to look for things that touched the crashreporter, which didn't show me much, so I expanded it to look at browser configs as well:
http://hg.mozilla.org/mozilla-central/log?rev=946ed22cad04431c75ab5093989dfedf1bae5a3e::afd82f887093%20and%20(file(%22glob:toolkit/crashreporter/**%22)%20or%20file(%22glob:browser/config/**%22))

...which turns up bug 1250709, which is a very plausible candiate to have broken this!

Comment 3

[(not currently active) Ted Mielczarek]

The first nightly with that change appears to be https://tools.taskcluster.net/index/artifacts/#gecko.v2.mozilla-central.nightly.2016.03.12.latest.firefox/gecko.v2.mozilla-central.nightly.2016.03.17.latest.firefox.linux64-opt

downloading the symbol file: https://queue.taskcluster.net/v1/task/ZPfR0fZhQgiaEuI0ey0yYg/artifacts/public%2Fbuild%2Ffirefox-48.0a1.en-US.linux-x86_64.crashreporter-symbols.zip

shows that it's missing the parameter list:
```
FUNC 1bc18e2 1a7 0 nsDragService::SetDragIcon
```

This shouldn't affect signature generation, since we already strip parameter lists for that, but it will impact readability of crash reports, since it'll be harder to differentiate function overloads.

I'm assuming this is just something different about gcc 4.9's DWARF generation that's breaking dump_syms.

Comment 4

[Mike Hommey [:glandium]]

Except bug 1250709 didn't change the compiler for firefox builds, it changed it for rooting hazard builds.

Comment 5

[(not currently active) Ted Mielczarek]

Oh, hah, yeah. That range also includes https://hg.mozilla.org/mozilla-central/rev/2d59367c985a (bug 1175546) (which wasn't showing up in my hg queries), which is probably it.