QML button without Icon creates a segfault in debug

Hi,

As discussed in the forum [here|https://forum.qt.io/topic/137554/button-segmentation-fault-qt-6-3-1/5,] it seems that multiple people are experiencing SegFault on Windows in QQuickIcon code with QML Button that have no icon field specified. Happens with very minimal QML code listed in the thread by OP.

Happened to me too on more complex code. The code was working fine with Qt6.2 before switching to 6.3.1 this week-end. Happens only in debug, with debugger attached. MSVC/CDB or MinGW/GDB, same thing.

The Icon object seems uninitialized, but the code is trying to set a qml watcher on it.
 
1 QArrayDataPointer<char16_t>::ref qarraydatapointer.h 325 0x7ffda6a4632c 2 QArrayDataPointer<char16_t>::QArrayDataPointer qarraydatapointer.h 71 0x7ffda6a4632c 3 QString::QString qstring.h 1242 0x7ffda6a4632c 4 QQuickIcon::name qquickicon.cpp 130 0x7ffda6a4632c 5 QQuickIcon::qt_static_metacall moc_qquickicon_p.cpp 88 0x7ffda6a4632c 6 QMetaProperty::read qmetaobject.cpp 3079 0x7ffd947e80dd 7 QQmlWatchProxy::notifyValueChanged qqmlwatcher.cpp 112 0x7ffdfd3b86f0 8 QQmlWatcher::addPropertyWatch qqmlwatcher.cpp 178 0x7ffdfd3b91d4 9 QQmlWatcher::addWatch qqmlwatcher.cpp 128 0x7ffdfd3b931c 10 QQmlEngineDebugServiceImpl::processMessage qqmlenginedebugservice.cpp 574 0x7ffdfd3b76fb 11 QtPrivate::QSlotObjectBase::call qobjectdefs_impl.h 399 0x7ffd9480f592 12 QMetaCallEvent::placeMetaCall qobject.cpp 624 0x7ffd9480f592 13 QObject::event qobject.cpp 1356 0x7ffd9480fdc4 14 QApplicationPrivate::notify_helper qapplication.cpp 3350 0x7ffd93c653b6 15 QCoreApplication::notifyInternal2 qcoreapplication.cpp 1067 0x7ffd947d91fd 16 QCoreApplication::sendEvent qcoreapplication.cpp 1483 0x7ffd947dcad9 17 QCoreApplicationPrivate::sendPostedEvents qcoreapplication.cpp 1845 0x7ffd947dcad9 18 QEventDispatcherWin32::sendPostedEvents qeventdispatcher_win.cpp 905 0x7ffd9495a37c 19 QWindowsGuiEventDispatcher::sendPostedEvents qwindowsguieventdispatcher.cpp 79 0x7ffd928dd6ce 20 QEventDispatcherWin32::processEvents qeventdispatcher_win.cpp 474 0x7ffd9495dfa8 21 QWindowsGuiEventDispatcher::processEvents qwindowsguieventdispatcher.cpp 72 0x7ffd928dd6b5 22 QEventLoop::processEvents qeventloop.cpp 136 0x7ffd947e40d4 23 QEventLoop::exec qeventloop.cpp 218 0x7ffd947e40d4 24 QCoreApplication::exec qflags.h 110 0x7ffd947e2719 25 QGuiApplication::exec qguiapplication.cpp 1887 0x7ffd925b65ff 26 QApplication::exec qapplication.cpp 2631 0x7ffd93c65327 27 qMain main.cpp 57 0x7ff731bb1c6b 28 WinMain qtentrypoint_win.cpp 50 0x7ff731bc4852 29 __tmainCRTStartup 0x7ff731bb1395 30 WinMainCRTStartup 0x7ff731bb14c6

 
 
{{this @0x1ade02a9330 QQuickIcon
d @0x1ade02a9330 QExplicitlySharedDataPointer<QQuickIconPrivate>
d @0x7ffd946c4cb0 QQuickIconPrivate
[QSharedData] ref: -1807034576 QSharedData
color @0x7ffd946c4ce8 QColor
cspec 2488347376 (2488347376) QColor::Spec
ct @0x7ffd946c4cec QColor::CT
height 32765 int name <inaccessible> QString
ownerAndCache @0x7ffd946c4cf8 QTaggedPointer<QObject, QQuickIconPrivate::CacheStatus>
resolveMask 32765 int resolvedSource <inaccessible> QUrl
source <inaccessible> QUrl
width -1806619952 int
}}