diff --git a/apps/openmw/mwgui/formatting.hpp b/apps/openmw/mwgui/formatting.hpp
index 3e21b62e2..5b7925057 100644
--- a/apps/openmw/mwgui/formatting.hpp
+++ b/apps/openmw/mwgui/formatting.hpp
@@ -132,6 +132,7 @@ namespace MWGui
                 virtual int pageSplit();
 
             protected:
+                virtual ~GraphicElement() {}
                 MyGUI::Widget * mParent;
                 Paginator & mPaginator;
                 BlockStyle mBlockStyle;
diff --git a/extern/ogre-ffmpeg-videoplayer/audiofactory.hpp b/extern/ogre-ffmpeg-videoplayer/audiofactory.hpp
index cf1ff46a8..06abd6a74 100644
--- a/extern/ogre-ffmpeg-videoplayer/audiofactory.hpp
+++ b/extern/ogre-ffmpeg-videoplayer/audiofactory.hpp
@@ -12,6 +12,7 @@ class MovieAudioFactory
 {
 public:
     virtual boost::shared_ptr<MovieAudioDecoder> createDecoder(VideoState* videoState) = 0;
+    virtual ~MovieAudioFactory() {}
 };
 
 }
diff --git a/extern/ogre-ffmpeg-videoplayer/videostate.cpp b/extern/ogre-ffmpeg-videoplayer/videostate.cpp
index c77723421..ece491edc 100644
--- a/extern/ogre-ffmpeg-videoplayer/videostate.cpp
+++ b/extern/ogre-ffmpeg-videoplayer/videostate.cpp
@@ -221,7 +221,7 @@ void VideoState::video_refresh()
     }
     else
     {
-        const float threshold = 0.03;
+        const float threshold = 0.03f;
         if (this->pictq[pictq_rindex].pts > this->get_master_clock() + threshold)
             return; // not ready yet to show this picture