fix some very minor memory leaks

src/PowderToySDL.cpp

@@ -334,6 +334,7 @@ int SDLOpen()
 #elif defined(LIN)
 	SDL_Surface *icon = SDL_CreateRGBSurfaceFrom((void*)app_icon, 48, 48, 24, 144, 0x00FF0000, 0x0000FF00, 0x000000FF, 0);
 	SDL_WM_SetIcon(icon, (Uint8*)app_icon_bitmap);
+	SDL_FreeSurface(icon);
 #endif
 
 	SDL_WM_SetCaption("The Powder Toy", "Powder Toy");

src/debug/DebugInfo.h

@@ -6,6 +6,7 @@ class DebugInfo
 {
 public:
 	DebugInfo(unsigned int id):ID(id) { }
+	virtual ~DebugInfo() { }
 	unsigned int ID;
 	virtual void Draw() {}
 };

src/gui/game/GameController.cpp

@@ -195,6 +195,10 @@ GameController::~GameController()
 	{
 		delete options;
 	}
+	for(std::vector<DebugInfo*>::iterator iter = debugInfo.begin(), end = debugInfo.end(); iter != end; iter++)
+	{
+		delete *iter;
+	}
 	//deleted here because it refuses to be deleted when deleted from gameModel even with the same code
 	std::deque<Snapshot*> history = gameModel->GetHistory();
 	for(std::deque<Snapshot*>::iterator iter = history.begin(), end = history.end(); iter != end; ++iter)

src/gui/game/QuickOption.h

@@ -37,8 +37,8 @@ protected:
 public:
 	virtual ~QuickOption()
 	{
-		//for(std::vector<QuickOptionListener*>::iterator iter = listeners.begin(), end = listeners.end(); iter != end; ++iter)
-		//	delete *iter;
+		for(std::vector<QuickOptionListener*>::iterator iter = listeners.begin(), end = listeners.end(); iter != end; ++iter)
+			delete *iter;
 	}
 
 	std::vector<QuickOptionListener*> GetListeners()

src/simulation/Gravity.cpp

@@ -60,6 +60,7 @@ void Gravity::gravity_init()
 
 void Gravity::gravity_cleanup()
 {
+	stop_grav_async();
 #ifdef GRAVFFT
 	grav_fft_cleanup();
 #endif