Fixed|Client: Crash during main window construction

It was possible that the log was flushed during construction of the
main window, which lead to the log alerter attempting to access a
partially constructed object.

Now ClientWindow::mainExists() only returns true if the main window
has been fully constructed.

doomsday/client/include/ui/clientwindow.h

@@ -170,6 +170,7 @@ class ClientWindow : public de::BaseWindow,
     bool handleFallbackEvent(de::Event const &event);
 
     static ClientWindow &main();
+    static bool mainExists();
 
 protected:
     bool prepareForDraw();

doomsday/client/src/ui/clientwindow.cpp

@@ -66,6 +66,8 @@ static inline InputSystem &inputSys()
     return ClientApp::inputSystem();
 }
 
+static ClientWindow *mainWindow = nullptr; // The main window, set after fully constructed.
+
 DENG2_PIMPL(ClientWindow)
 , DENG2_OBSERVES(MouseEventSource, MouseStateChange)
 , DENG2_OBSERVES(Canvas, FocusChange)
@@ -151,6 +153,11 @@ DENG2_PIMPL(ClientWindow)
 
         releaseRef(cursorX);
         releaseRef(cursorY);
+
+        if(thisPublic == mainWindow)
+        {
+            mainWindow = nullptr;
+        }
     }
 
     Widget &container()
@@ -736,6 +743,12 @@ ClientWindow::ClientWindow(String const &id)
 #endif
 
     d->setupUI();
+
+    // The first window is the main window.
+    if(!mainWindow)
+    {
+        mainWindow = this;
+    }
 }
 
 Vector2f ClientWindow::windowContentSize() const
@@ -1036,6 +1049,11 @@ ClientWindow &ClientWindow::main()
     return static_cast<ClientWindow &>(BaseWindow::main());
 }
 
+bool ClientWindow::mainExists()
+{
+    return mainWindow != nullptr;
+}
+
 void ClientWindow::toggleFPSCounter()
 {
     App::config().set(configName("showFps"), !isFPSCounterVisible());

doomsday/config_win32.pri

@@ -36,6 +36,11 @@ deng_msvc {
     QMAKE_RC = $$QMAKE_RC /I \"$$DENG_API_DIR\"
 
     deng_debug: QMAKE_RC = $$QMAKE_RC /d _DEBUG
+
+    !deng_debug:deng_debuginfo {
+        QMAKE_CFLAGS += -Z7 -DEBUG
+        QMAKE_CXXFLAGS += -Z7 -DEBUG
+    }
 }
 deng_mingw {
     QMAKE_RC = $$QMAKE_RC --include-dir=\"$$DENG_API_DIR\"