#0  calculate_vertex_layout (i915=0xabde00)
    at /var/tmp/portage/media-libs/mesa-17.1.0_rc4/work/mesa-17.1.0-rc4/src/gallium/drivers/i915/i915_state_derived.c:72
#1  0x00007fffd98c9b86 in i915_update_derived (
    i915=i915@entry=0xabde00)
    at /var/tmp/portage/media-libs/mesa-17.1.0_rc4/work/mesa-17.1.0-rc4/src/gallium/drivers/i915/i915_state_derived.c:221
#2  0x00007fffd98b7a5a in i915_clear_render (pipe=0xabde00, 
    buffers=7, color=0xbbb08c, depth=1, stencil=0)
    at /var/tmp/portage/media-libs/mesa-17.1.0_rc4/work/mesa-17.1.0-rc4/src/gallium/drivers/i915/i915_clear.c:254
#3  0x00007fffd960dd31 in st_Clear (ctx=0xbb9550, mask=304)
    at /var/tmp/portage/media-libs/mesa-17.1.0_rc4/work/mesa-17.1.0-rc4/src/mesa/state_tracker/st_cb_clear.c:481
#4  0x00007fffef439a0d in QOpenGLFunctions::glClear (
    mask=17664, this=<optimized out>)
    at ../../include/QtGui/../../src/gui/opengl/qopenglfunctions.h:620
#5  QOpenGLWidgetPrivate::recreateFbo (
    this=this@entry=0x9448a0) at kernel/qopenglwidget.cpp:713
#6  0x00007fffef43a1a8 in QOpenGLWidget::resizeEvent (
    this=this@entry=0x944810, e=<optimized out>)
    at kernel/qopenglwidget.cpp:1181
#7  0x00007ffff7fcf34d in QtWebEngineCore::RenderWidgetHostViewQtDelegateWidget::resizeEvent (this=0x944810, 
    resizeEvent=<optimized out>)
    at render_widget_host_view_qt_delegate_widget.cpp:272
#8  0x00007fffef41927e in QWidget::event (
    this=this@entry=0x944810, 
    event=event@entry=0x7fffffffcc80)
    at kernel/qwidget.cpp:8946
#9  0x00007fffef43b583 in QOpenGLWidget::event (
    this=this@entry=0x944810, e=e@entry=0x7fffffffcc80)
    at kernel/qopenglwidget.cpp:1350
#10 0x00007ffff7fcf62b in QtWebEngineCore::RenderWidgetHostViewQtDelegateWidget::event (this=0x944810, event=0x7fffffffcc80)
    at render_widget_host_view_qt_delegate_widget.cpp:363
#11 0x00007fffef3c87a4 in QApplicationPrivate::notify_helper (
    this=<optimized out>, receiver=0x944810, e=0x7fffffffcc80)
    at kernel/qapplication.cpp:3799
#12 0x00007fffef3d041d in QApplication::notify (
    this=0x7fffffffdee0, receiver=0x944810, e=0x7fffffffcc80)
    at kernel/qapplication.cpp:3556
#13 0x00007fffef00a14a in QCoreApplication::notifyInternal2 (
    receiver=receiver@entry=0x944810, 
    event=event@entry=0x7fffffffcc80)
    at kernel/qcoreapplication.cpp:988
#14 0x00007fffef411212 in QCoreApplication::sendEvent (
    event=0x7fffffffcc80, receiver=0x944810)
    at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:231
#15 QWidgetPrivate::sendPendingMoveAndResizeEvents (
    this=this@entry=0x9448a0, 
    recursive=recursive@entry=false, 
    disableUpdates=<optimized out>, 
    disableUpdates@entry=false) at kernel/qwidget.cpp:7809
#16 0x00007fffef4154f3 in QWidgetPrivate::show_helper (
    this=0x9448a0) at kernel/qwidget.cpp:7860
#17 0x00007fffef41531b in QWidgetPrivate::show_recursive (
    this=<optimized out>) at kernel/qwidget.cpp:7790
#18 0x00007fffef415450 in QWidgetPrivate::showChildren (
    this=this@entry=0x92e7f0, 
    spontaneous=spontaneous@entry=false)
    at kernel/qwidget.cpp:8296
#19 0x00007fffef41550f in QWidgetPrivate::show_helper (
    this=this@entry=0x92e7f0) at kernel/qwidget.cpp:7866
#20 0x00007fffef4188a4 in QWidget::setVisible (this=0x930540, 
    visible=<optimized out>) at kernel/qwidget.cpp:8215
#21 0x00007fffef415468 in QWidgetPrivate::showChildren (
    this=this@entry=0x979d40, 
    spontaneous=spontaneous@entry=false)
    at kernel/qwidget.cpp:8298
#22 0x00007fffef41550f in QWidgetPrivate::show_helper (
    this=this@entry=0x979d40) at kernel/qwidget.cpp:7866
#23 0x00007fffef4188a4 in QWidget::setVisible (this=0x97a370, 
    visible=<optimized out>) at kernel/qwidget.cpp:8215
#24 0x00007fffef415468 in QWidgetPrivate::showChildren (
    this=this@entry=0x961d30, 
    spontaneous=spontaneous@entry=false)
    at kernel/qwidget.cpp:8298
#25 0x00007fffef41550f in QWidgetPrivate::show_helper (
    this=this@entry=0x961d30) at kernel/qwidget.cpp:7866
#26 0x00007fffef4188a4 in QWidget::setVisible (this=0x9798f0, 
    visible=<optimized out>) at kernel/qwidget.cpp:8215
#27 0x00007fffef415468 in QWidgetPrivate::showChildren (
    this=this@entry=0x930330, 
    spontaneous=spontaneous@entry=false)
    at kernel/qwidget.cpp:8298
#28 0x00007fffef41550f in QWidgetPrivate::show_helper (
    this=this@entry=0x930330) at kernel/qwidget.cpp:7866
#29 0x00007fffef4188a4 in QWidget::setVisible (this=0x930280, 
    visible=<optimized out>) at kernel/qwidget.cpp:8215
#30 0x00007fffef3f75c7 in QStackedLayout::setCurrentIndex (
    this=0x7d2190, index=0) at kernel/qstackedlayout.cpp:321
#31 0x00007fffef3f7e2a in QStackedLayout::insertWidget (
    this=0x7d2190, index=0, widget=0x930280)
    at kernel/qstackedlayout.cpp:231
#32 0x00007ffff7a43f6f in TabStackedWidget::insertTab(int, QWidget*, QString const&, bool) ()
   from /usr/lib64/libQupZilla.so.2
#33 0x00007ffff7a44f60 in TabWidget::addView(LoadRequest const&, QString const&, QFlags<Qz::NewTabPositionFlag> const&, bool, int, bool) () from /usr/lib64/libQupZilla.so.2
#34 0x00007ffff7a454a5 in TabWidget::addView(LoadRequest const&, QFlags<Qz::NewTabPositionFlag> const&, bool, bool) ()
   from /usr/lib64/libQupZilla.so.2
#35 0x00007ffff7925a3d in BrowserWindow::postLaunch() ()
   from /usr/lib64/libQupZilla.so.2
#36 0x00007fffef038869 in QObject::event (
    this=this@entry=0x72d090, e=e@entry=0x8b3c50)
    at kernel/qobject.cpp:1263
#37 0x00007fffef419003 in QWidget::event (
    this=this@entry=0x72d090, event=event@entry=0x8b3c50)
    at kernel/qwidget.cpp:9225
#38 0x00007fffef525a7b in QMainWindow::event (this=0x72d090, 
    event=0x8b3c50) at widgets/qmainwindow.cpp:1543
#39 0x00007fffef3c87a4 in QApplicationPrivate::notify_helper (
    this=<optimized out>, receiver=0x72d090, e=0x8b3c50)
    at kernel/qapplication.cpp:3799
#40 0x00007fffef3d041d in QApplication::notify (
    this=0x7fffffffdee0, receiver=0x72d090, e=0x8b3c50)
    at kernel/qapplication.cpp:3556
#41 0x00007fffef00a14a in QCoreApplication::notifyInternal2 (
    receiver=0x72d090, event=event@entry=0x8b3c50)
    at kernel/qcoreapplication.cpp:988
#42 0x00007fffef00ceb6 in QCoreApplication::sendEvent (
    event=0x8b3c50, receiver=<optimized out>)
    at kernel/qcoreapplication.h:231
#43 QCoreApplicationPrivate::sendPostedEvents (
    receiver=receiver@entry=0x0, 
    event_type=event_type@entry=0, data=0x646d50)
    at kernel/qcoreapplication.cpp:1649
#44 0x00007fffef00d408 in QCoreApplication::sendPostedEvents (
    receiver=receiver@entry=0x0, 
    event_type=event_type@entry=0)
    at kernel/qcoreapplication.cpp:1503
#45 0x00007fffef061cf3 in postEventSourceDispatch (s=0x69b870)
    at kernel/qeventdispatcher_glib.cpp:276
#46 0x00007fffec684437 in g_main_dispatch (
    context=0x7fffd40016f0)
    at /var/tmp/portage/dev-libs/glib-2.50.3-r1/work/glib-2.50.3/glib/gmain.c:3203
#47 g_main_context_dispatch (
    context=context@entry=0x7fffd40016f0)
    at /var/tmp/portage/dev-libs/glib-2.50.3-r1/work/glib-2.50.3/glib/gmain.c:3856
#48 0x00007fffec6846a0 in g_main_context_iterate (
    context=context@entry=0x7fffd40016f0, 
    block=block@entry=1, dispatch=dispatch@entry=1, 
    self=<optimized out>)
    at /var/tmp/portage/dev-libs/glib-2.50.3-r1/work/glib-2.50.3/glib/gmain.c:3929
#49 0x00007fffec68474c in g_main_context_iteration (
    context=0x7fffd40016f0, may_block=may_block@entry=1)
    at /var/tmp/portage/dev-libs/glib-2.50.3-r1/work/glib-2.50.3/glib/gmain.c:3990
#50 0x00007fffef061d6f in QEventDispatcherGlib::processEvents
    (this=0x689d70, flags=...)
    at kernel/qeventdispatcher_glib.cpp:423
#51 0x00007fffef008842 in QEventLoop::exec (
    this=this@entry=0x7fffffffdd70, flags=..., 
    flags@entry=...) at kernel/qeventloop.cpp:212
#52 0x00007fffef01143c in QCoreApplication::exec ()
    at kernel/qcoreapplication.cpp:1261
#53 0x0000000000402984 in ?? ()
#54 0x0000000000000001 in ?? ()
#55 0x00007fffffffde20 in ?? ()
#56 0x00007fffffffde30 in ?? ()
#57 0x00050701f7ff6660 in ?? ()
#58 0x00007fffffffde10 in ?? ()
#59 0x0000000100050600 in ?? ()
#60 0x00000000006418e0 in ?? ()
#61 0x00007ffff7ff69b8 in ?? ()
#62 0x000000000063fe80 in ?? ()
#63 0x0000000000605240 in ?? ()
#64 0x00000000006443d0 in ?? ()
#65 0x00000000006050f0 in ?? ()
#66 0x000000000063b320 in ?? ()
#67 0x00007fffffffe0d8 in ?? ()
#68 0x000000000063e7a0 in ?? ()
#69 0x0000000000000001 in ?? ()
#70 0x000000000063e7d0 in ?? ()
#71 0x00007ffff7de88c4 in _dl_fixup (l=<optimized out>, 
    reloc_arg=<optimized out>) at ../elf/dl-runtime.c:111
#72 0x00007ffff7df004f in _dl_runtime_resolve_sse ()
    at ../sysdeps/x86_64/dl-trampoline.h:211
#73 0x0000000000402c8a in ?? ()
#74 0x00007fffffffe0b8 in ?? ()
#75 0x000000000000001c in ?? ()
#76 0x0000000000000001 in ?? ()
#77 0x00007fffffffe3a7 in ?? ()
#78 0x0000000000000000 in ?? ()