qt: Delete splash screen widget explicitly

This ensures that during shutdown, including failed initialization, the
`SplashScreen::m_connected_wallet_handlers` is deleted before the wallet
context is.

Author: hebasto

src/qt/bitcoin.cpp

@@ -311,11 +311,8 @@ void BitcoinApplication::createSplashScreen(const NetworkStyle *networkStyle)
 {
     assert(!m_splash);
     m_splash = new SplashScreen(networkStyle);
-    // We don't hold a direct pointer to the splash screen after creation, but the splash
-    // screen will take care of deleting itself when finish() happens.
     m_splash->show();
     connect(this, &BitcoinApplication::splashFinished, m_splash, &SplashScreen::finish);
-    connect(this, &BitcoinApplication::requestedShutdown, m_splash, &QWidget::close);
 }
 
 void BitcoinApplication::createNode(interfaces::Init& init)
@@ -373,6 +370,9 @@ void BitcoinApplication::requestShutdown()
         w->hide();
     }
 
+    delete m_splash;
+    m_splash = nullptr;
+
     // Show a simple window indicating shutdown status
     // Do this first as some of the steps may take some time below,
     // for example the RPC console may still be executing a command.
@@ -412,10 +412,13 @@ void BitcoinApplication::requestShutdown()
 void BitcoinApplication::initializeResult(bool success, interfaces::BlockAndHeaderTipInfo tip_info)
 {
     qDebug() << __func__ << ": Initialization result: " << success;
+
     // Set exit result.
     returnValue = success ? EXIT_SUCCESS : EXIT_FAILURE;
-    if(success)
-    {
+    if(success) {
+        delete m_splash;
+        m_splash = nullptr;
+
         // Log this only after AppInitMain finishes, as then logging setup is guaranteed complete
         qInfo() << "Platform customization:" << platformStyle->getName();
         clientModel = new ClientModel(node(), optionsModel);
@@ -438,7 +441,6 @@ void BitcoinApplication::initializeResult(bool success, interfaces::BlockAndHead
         } else {
             window->showMinimized();
         }
-        Q_EMIT splashFinished();
         Q_EMIT windowShown(window);
 
 #ifdef ENABLE_WALLET
@@ -455,7 +457,6 @@ void BitcoinApplication::initializeResult(bool success, interfaces::BlockAndHead
 #endif
         pollShutdownTimer->start(SHUTDOWN_POLLING_DELAY);
     } else {
-        Q_EMIT splashFinished(); // Make sure splash screen doesn't stick around during shutdown
         requestShutdown();
     }
 }