browser crashes on qt5.2

[Bill Filler]

Testing qt5.2 using steps in PPA:
https://launchpad.net/~canonical-qt5-edgers/+archive/qt5-beta2

browser crashes on startup, with this error:
ASSERTION FAILED: isPointerTypeAlignmentOkay(reinterpret_cast<TypePtr>(ptr))
../WTF/wtf/StdLibExtras.h(95) : TypePtr reinterpret_cast_ptr(void*) [with TypePtr = long long unsigned int*]
Segmentation fault (core dumped)

gdb shows something in QtWebKit

Program terminated with signal SIGSEGV, Segmentation fault.
#0 0x48536486 in WTFCrash () from /usr/lib/arm-linux-gnueabihf/libQt5WebKit.so.5
(gdb) bt
#0 0x48536486 in WTFCrash () from /usr/lib/arm-linux-gnueabihf/libQt5WebKit.so.5
#1 0x46afc42e in ?? () from /usr/lib/arm-linux-gnueabihf/libQt5WebKit.so.5

[Olivier Tilloy (osomon)]

It looks like this is the same crash we were seeing on armhf in bug #1271033.

[Olivier Tilloy (osomon)]

This is a partial stack trace I managed to get for this crash on my device. gdb eventually gets killed by the OOM killer so I’m not getting a full stacktrace, but this should be enough to allow investigating where the issue is.

#0 0x49e36486 in WTFCrash ()
   from /usr/lib/arm-linux-gnueabihf/libQt5WebKit.so.5
#1 0x483fc42e in CoreIPC::ArgumentEncoder::encode (this=0x0, n=10)
    at ../WTF/wtf/StdLibExtras.h:95
#2 0x483fc44e in CoreIPC::ArgumentEncoder::encodeVariableLengthByteArray (
    this=0x4f1a0610, dataReference=...)
    at Platform/CoreIPC/ArgumentEncoder.cpp:127
#3 0x48409428 in CoreIPC::StringReference::encode (this=0x0, encoder=...)
    at Platform/CoreIPC/ArgumentCoder.h:39
#4 0x484066ec in CoreIPC::MessageEncoder::MessageEncoder (this=0x4f1a0610,
    messageReceiverName=..., messageName=..., destinationID=0)
    at Platform/CoreIPC/ArgumentCoder.h:39
#5 0x48406766 in CoreIPC::MessageEncoder::create (messageReceiverName=...,
    messageName=..., destinationID=0)
    at Platform/CoreIPC/MessageEncoder.cpp:39
#6 0x4849fb98 in WebKit::ChildProcessProxy::send<Messages::WebProcess::InitializeWebProcess> (this=0x4f19e390, message=...,
    destinationID=5328631749368872970, messageSendFlags=0)
    at Shared/ChildProcessProxy.h:97
#7 0x484a510a in WebKit::WebContext::createNewWebProcess (this=0x4f19bf28)
    at UIProcess/WebContext.cpp:553
#8 0x484a5526 in WebKit::WebContext::ensureSharedWebProcess (this=0x4f19bf28)
    at UIProcess/WebContext.cpp:471
#9 0x484a579e in WebKit::WebContext::createWebPage (this=0x4f19bf28,

[Olivier Tilloy (osomon)]

It could very well be this upstream bug: https://bugs.webkit.org/show_bug.cgi?id=125674.

[Olivier Tilloy (osomon)]

I can confirm that this is indeed this upstream bug, Timo rebuilt QtWebKit with the corresponding patch and the crash goes away.

[Timo Jyrinki (timo-jyrinki)]

5.2.0-0ubuntu1~trusty1~test3 copied to qt5-beta2 PPA.

Meanwhile also tested rebuilding webbrowser-app despite the current lack of builders, but it did build for armhf and eyes can rest on this successful build (including tests, ie. bug #1271033) at https://launchpad.net/~canonical-qt5-edgers/+archive/qt5-daily/+build/5556909

[Timo Jyrinki (timo-jyrinki)]

Confirming successful browsing!