Enable warnings for non virtual destructors.

src/backgroundthread.h

@@ -10,6 +10,7 @@ class BackgroundThreadBase : public QThread {
   Q_OBJECT
  public:
   BackgroundThreadBase(QObject* parent = 0) : QThread(parent) {}
+  virtual ~BackgroundThreadBase() {}
  signals:
   void Initialised();
 };
@@ -18,7 +19,7 @@ template <typename T>
 class BackgroundThread : public BackgroundThreadBase {
  public:
   BackgroundThread(QObject* parent = 0);
-  ~BackgroundThread();
+  virtual ~BackgroundThread();
 
   boost::shared_ptr<T> Worker() const { return worker_; }
 

src/src.pro

@@ -137,6 +137,9 @@ win32|fedora-win32-cross {
 # Last.fm
 LIBS += -llastfm
 
+# Enable a bunch of warnings
+QMAKE_CXXFLAGS += -Wall -Werror=non-virtual-dtor -Woverloaded-virtual
+
 # Other platform specific libraries
 !win32:!fedora-win32-cross { 
     mac {