--- ./src/gui/kernel/qeventdispatcher_mac.mm	2015-01-04 23:35:52.000000000 -0500
+++ ./src/gui/kernel/qeventdispatcher_mac.mm	2015-01-04 23:48:08.000000000 -0500
@@ -558,7 +558,6 @@
 
     // In case we end up recursing while we now process events, make sure
     // that we send remaining posted Qt events before this call returns:
-    wakeUp();
     emit awake();
 
     bool excludeUserEvents = flags & QEventLoop::ExcludeUserInputEvents;
@@ -600,14 +599,45 @@
             // [NSApplication run], which is the normal code path for cocoa applications.
             if (NSModalSession session = d->currentModalSession()) {
                 QBoolBlocker execGuard(d->currentExecIsNSAppRun, false);
-                while ([[NSApplication sharedApplication] runModalSession:session] == NSRunContinuesResponse && !d->interrupt)
-                    qt_mac_waitForMoreModalSessionEvents();
+
+                // OSX 10.9 appears to tighten up its internal code such that
+                // sessions shouldn't be used once they've been freed, which
+                // could happen in the else condition of the if(canExec)
+                // statement. Add extra logic to make sure we don't use the
+                // session once the current modal session is freed. We stop if
+                // the session is no longer current or if runModalSession()
+                // indicates the modal session is no longer continuing.
+                bool stayInLoop = true;
+                while (!d->interrupt && stayInLoop) {
+                    // Mavericks deprecated the status we wish to check.
+                    NSInteger checkStatus = 0;
+#if defined(QT_MAC_USE_COCOA) && MAC_OS_X_VERSION_MAX_ALLOWED <= MAC_OS_X_VERSION_10_8
+                    checkStatus = NSRunContinuesResponse;
+#else
+                    checkStatus = NSModalResponseContinue;
+#endif
+                    if([NSApp runModalSession:session] == checkStatus) {
+                        qt_mac_waitForMoreModalSessionEvents();
+                    }
+                    else {
+                        stayInLoop = false;
+                    }
+
+                    if(session != d->currentModalSession()) {
+                        stayInLoop = false;
+                    }
+                }
 
                 if (!d->interrupt && session == d->currentModalSessionCached) {
                     // Someone called [[NSApplication sharedApplication] stopModal:] from outside the event
                     // dispatcher (e.g to stop a native dialog). But that call wrongly stopped
                     // 'session' as well. As a result, we need to restart all internal sessions:
                     d->temporarilyStopAllModalSessions();
+
+                    // Clean up the modal session list, call endModalSession.
+                    if (d->cleanupModalSessionsNeeded) {
+                        d->cleanupModalSessions();
+                    }
                 }
             } else {
                 d->nsAppRunCalledByQt = true;
@@ -626,12 +656,25 @@
                     // to use cocoa's native way of running modal sessions:
                     if (flags & QEventLoop::WaitForMoreEvents)
                         qt_mac_waitForMoreModalSessionEvents();
+
+                    // Mavericks deprecated the status we wish to check.
+                    NSInteger checkStatus = 0;
+#if defined(QT_MAC_USE_COCOA) && MAC_OS_X_VERSION_MAX_ALLOWED <= MAC_OS_X_VERSION_10_8
+                    checkStatus = NSRunContinuesResponse;
+#else
+                    checkStatus = NSModalResponseContinue;
+#endif
                     NSInteger status = [[NSApplication sharedApplication] runModalSession:session];
-                    if (status != NSRunContinuesResponse && session == d->currentModalSessionCached) {
+                    if (status != checkStatus && session == d->currentModalSessionCached) {
                         // INVARIANT: Someone called [NSApplication stopModal:] from outside the event
                         // dispatcher (e.g to stop a native dialog). But that call wrongly stopped
                         // 'session' as well. As a result, we need to restart all internal sessions:
                         d->temporarilyStopAllModalSessions();
+
+                        // Clean up the modal seesion list, call endModalSession.
+                        if (d->cleanupModalSessionsNeeded) {
+                            d->cleanupModalSessions();
+                        }
                     }
                     retVal = true;
                 } else do {
@@ -823,6 +866,7 @@
         if (info.session) {
             [[NSApplication sharedApplication] endModalSession:info.session];
             info.session = 0;
+            [(NSWindow*) info.nswindow release];
         }
     }
     currentModalSessionCached = 0;
@@ -923,12 +967,15 @@
             currentModalSessionCached = info.session;
             break;
         }
-        cocoaModalSessionStack.remove(i);
         currentModalSessionCached = 0;
         if (info.session) {
+            Q_ASSERT(info.nswindow != 0);
             [[NSApplication sharedApplication] endModalSession:info.session];
             [(NSWindow *)info.nswindow release];
         }
+
+        // remove the info now that we are finished with it
+        cocoaModalSessionStack.remove(i);
     }
 
     updateChildrenWorksWhenModal();
@@ -937,6 +984,8 @@
 
 void QEventDispatcherMacPrivate::beginModalSession(QWidget *widget)
 {
+    QEventDispatcherMac::instance()->interrupt();
+
     // Add a new, empty (null), NSModalSession to the stack.
     // It will become active the next time QEventDispatcher::processEvents is called.
     // A QCocoaModalSessionInfo is considered pending to become active if the widget pointer 
@@ -958,16 +1007,20 @@
     // when we stop the _current_ modal session (which is the session on top of
     // the stack, and might not belong to 'widget'). 
     int stackSize = cocoaModalSessionStack.size();
+    int endedSessions = 0;
     for (int i=stackSize-1; i>=0; --i) {
         QCocoaModalSessionInfo &info = cocoaModalSessionStack[i];
+        if (!info.widget) {
+            endedSessions++;
+        }
         if (info.widget == widget) {
             info.widget = 0;
-            if (i == stackSize-1) {
+            if (i + endedSessions == stackSize-1) {
                 // The top sessions ended. Interrupt the event dispatcher
                 // to start spinning the correct session immidiatly: 
+                QEventDispatcherMac::instance()->interrupt();
                 currentModalSessionCached = 0;
                 cleanupModalSessionsNeeded = true;
-                QEventDispatcherMac::instance()->interrupt();
             }
         }
     }
@@ -1044,8 +1097,9 @@
     }
 
 #ifdef QT_MAC_USE_COCOA
-    if (d->cleanupModalSessionsNeeded)
+    if (d->cleanupModalSessionsNeeded && d->currentExecIsNSAppRun) {
         d->cleanupModalSessions();
+    }
 #endif
 
     if (d->interrupt) {
@@ -1055,8 +1109,9 @@
             // [NSApplication run] is running the event loop, we
             // delayed stopping it until now (to let cocoa process 
             // pending cocoa events first).
-            if (d->currentModalSessionCached)
+            if (d->currentModalSessionCached) {
                 d->temporarilyStopAllModalSessions();
+            }
             [[NSApplication sharedApplication] stop:[NSApplication sharedApplication]];
             d->cancelWaitForMoreEvents();
         }