gui: Crash if shutdown during processNewTransaction #18090

i.e call generatetoaddress and shutdown bitcoin-qt:

* thread [#1](/bitcoin-bitcoin/1/), queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x45)
    frame [#0](/bitcoin-bitcoin/0/): 0x0000000100268cae bitcoin-qt`WalletView::processNewTransaction(this=0x00000001280ce250, parent=0x00007ffeefbfcf78, start=3, (null)=3) at walletview.cpp:136:61
   133 	void WalletView::processNewTransaction(const QModelIndex& parent, int start, int /*end*/)
   134 	{
   135 	    // Prevent balloon-spam when initial block download is in progress
-> 136 	    if (!walletModel || !clientModel || clientModel->node().isInitialBlockDownload())
   137 	        return;
   138 	
   139 	    TransactionTableModel *ttm = walletModel->getTransactionTableModel();
Target 0: (bitcoin-qt) stopped.

* thread [#1](/bitcoin-bitcoin/1/), queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x45)
  * frame [#0](/bitcoin-bitcoin/0/): 0x0000000100268c7d bitcoin-qt`WalletView::processNewTransaction(this=0x000000010df82250, parent=0x00007ffeefbfcf78, start=19, (null)=19) at walletview.cpp:139:50
    frame [#1](/bitcoin-bitcoin/1/): 0x000000010026c134 bitcoin-qt`QtPrivate::FunctorCall<QtPrivate::IndexesList<0, 1, 2>, QtPrivate::List<QModelIndex const&, int, int>, void, void (WalletView::*)(QModelIndex const&, int, int)>::call(f=f0 8b 26 00 01 00 00 00 00 00 00 00 00 00 00 00, o=0x000000010df82250, arg=0x00007ffeefbfcfb0)(QModelIndex const&, int, int), WalletView*, void**) at qobjectdefs_impl.h:152:13
    frame [#2](/bitcoin-bitcoin/2/): 0x000000010026c006 bitcoin-qt`void QtPrivate::FunctionPointer<void (WalletView::*)(QModelIndex const&, int, int)>::call<QtPrivate::List<QModelIndex const&, int, int>, void>(f=f0 8b 26 00 01 00 00 00 00 00 00 00 00 00 00 00, o=0x000000010df82250, arg=0x00007ffeefbfcfb0)(QModelIndex const&, int, int), WalletView*, void**) at qobjectdefs_impl.h:185:13
    frame [#3](/bitcoin-bitcoin/3/): 0x000000010026bec4 bitcoin-qt`QtPrivate::QSlotObject<void (WalletView::*)(QModelIndex const&, int, int), QtPrivate::List<QModelIndex const&, int, int>, void>::impl(which=1, this_=0x0000000127e5f2a0, r=0x000000010df82250, a=0x00007ffeefbfcfb0, ret=0x0000000000000000) at qobjectdefs_impl.h:414:17
    frame [#4](/bitcoin-bitcoin/4/): 0x0000000104e326e2 QtCore`___lldb_unnamed_symbol2576$$QtCore + 1138
    frame [#5](/bitcoin-bitcoin/5/): 0x0000000104db29c0 QtCore`QAbstractItemModel::endInsertRows() + 272
    frame [#6](/bitcoin-bitcoin/6/): 0x00000001001e375f bitcoin-qt`TransactionTablePriv::updateWallet(this=0x000000012af59850, wallet=0x000000012af15d50, hash=0x00007ffeefbfd498, status=0, showTransaction=true) at transactiontablemodel.cpp:147:29
    frame [#7](/bitcoin-bitcoin/7/): 0x00000001001e2a7b bitcoin-qt`TransactionTableModel::updateTransaction(this=0x000000012af59710, hash=0x000000010560c830, status=0, showTransaction=true) at transactiontablemodel.cpp:251:11
    frame [#8](/bitcoin-bitcoin/8/): 0x000000010027dcdd bitcoin-qt`TransactionTableModel::qt_static_metacall(_o=0x000000012af59710, _c=InvokeMetaMethod, _id=0, _a=0x00000001056202b0) at moc_transactiontablemodel.cpp:91:21
    frame [#9](/bitcoin-bitcoin/9/): 0x0000000104e2addd QtCore`QObject::event(QEvent*) + 957
    frame [#10](/bitcoin-bitcoin/10/): 0x0000000104082bcd QtWidgets`QApplicationPrivate::notify_helper(QObject*, QEvent*) + 269
    frame [#11](/bitcoin-bitcoin/11/): 0x0000000104084005 QtWidgets`QApplication::notify(QObject*, QEvent*) + 581
    frame [#12](/bitcoin-bitcoin/12/): 0x0000000104e00994 QtCore`QCoreApplication::notifyInternal2(QObject*, QEvent*) + 212
    frame [#13](/bitcoin-bitcoin/13/): 0x0000000104e01a43 QtCore`QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) + 691

I can't reproduce. Have you called the command from the GUI console or through the RPC interface? When I do it over the GUI console my bitcoin-qt freezes and the shutdown happens after everything's finished

Can reproduce it through the RPC interface

Reproduce in GUI:

• open console
• generatetoaddress(1000,getnewaddress())
• Quit Bitcoin-Qt
• segfault

@jonasschnelli My Computer freezes during generatetoaddress is executed. I can't close bitcoin-qt then. Well it works when calling the command through bitcoin-cli.