diff --git a/CMakeLists.txt b/CMakeLists.txt
index 16380bc26..268449e14 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -103,6 +103,11 @@ if (APPLE)
   )
 endif (APPLE)
 
+# Compiler settings
+if (CMAKE_COMPILER_IS_GNUCC)
+    add_definitions (-Wall)
+endif (CMAKE_COMPILER_IS_GNUCC)
+
 # Main executable
 add_executable(openmw
     MACOSX_BUNDLE
diff --git a/bsa/bsa_file.cpp b/bsa/bsa_file.cpp
index 7a7600ad1..a6bf47848 100644
--- a/bsa/bsa_file.cpp
+++ b/bsa/bsa_file.cpp
@@ -129,7 +129,7 @@ void BSAFile::readHeader()
 
   // Set up the the FileStruct table
   files.resize(filenum);
-  for(int i=0;i<filenum;i++)
+  for(size_t i=0;i<filenum;i++)
     {
       FileStruct &fs = files[i];
       fs.fileSize = offsets[i*2];
@@ -156,7 +156,7 @@ int BSAFile::getIndex(const char *str)
   else
     {
       int res = it->second;
-      assert(res >= 0 && res < files.size());
+      assert(res >= 0 && res < static_cast<int> (files.size()));
       return res;
     }
 }
diff --git a/esm/esm_reader.hpp b/esm/esm_reader.hpp
index 52f67fea0..85d956689 100644
--- a/esm/esm_reader.hpp
+++ b/esm/esm_reader.hpp
@@ -394,7 +394,7 @@ public:
   void getHExact(void*p, int size)
   {
     getSubHeader();
-    if(size != c.leftSub)
+    if(size !=static_cast<int> (c.leftSub))
       fail("getHExact() size mismatch");
     getExact(p,size);
   }
@@ -480,7 +480,7 @@ public:
   void skipHSubSize(int size)
     {
       skipHSub();
-      if(c.leftSub != size)
+      if(static_cast<int> (c.leftSub) != size)
 	fail("skipHSubSize() mismatch");
     }
 
@@ -508,7 +508,7 @@ public:
   void getSubHeaderIs(int size)
   {
     getSubHeader();
-    if(size != c.leftSub)
+    if(size != static_cast<int> (c.leftSub))
       fail("getSubHeaderIs(): Sub header mismatch");
   }
 
diff --git a/game/mwrender/playerpos.hpp b/game/mwrender/playerpos.hpp
index cf1d02092..47175651c 100644
--- a/game/mwrender/playerpos.hpp
+++ b/game/mwrender/playerpos.hpp
@@ -15,7 +15,7 @@ namespace MWRender
 
   public:
     PlayerPos(Ogre::Camera *cam) :
-      camera(cam), x(0), y(0), z(0) {}
+      x(0), y(0), z(0), camera(cam) {}
 
     // Set the player position. Uses Morrowind coordinates.
     void setPos(float _x, float _y, float _z)
diff --git a/input/listener.hpp b/input/listener.hpp
index 5b9d4fb49..ef4cce57f 100644
--- a/input/listener.hpp
+++ b/input/listener.hpp
@@ -17,7 +17,7 @@ namespace Input
     InputListener(Render::OgreRenderer &rend,
                   Input::OISManager &input,
                   const Input::Dispatcher &_disp)
-      : doExit(false), disp(_disp)
+      : disp(_disp), doExit(false)
     {
       // Set up component pointers
       mWindow = rend.getWindow();
diff --git a/nif/data.hpp b/nif/data.hpp
index d7d233dff..920c7cf45 100644
--- a/nif/data.hpp
+++ b/nif/data.hpp
@@ -198,7 +198,7 @@ struct NiPosData : Record
     // translation in NiKeyframeData.
     for(int i=0; i<count; i++)
       {
-        float time = nif->getFloat();
+        /*float time =*/ nif->getFloat();
         nif->getVector(); // This isn't really shared between type 1
                           // and type 2, most likely
         if(type == 2)
@@ -267,14 +267,14 @@ struct NiPixelData : Record
     mips = nif->getInt();
 
     // Bytes per pixel, should be bpp * 8
-    int bytes = nif->getInt();
+    /*int bytes =*/ nif->getInt();
 
     for(int i=0; i<mips; i++)
       {
         // Image size and offset in the following data field
-        int x = nif->getInt();
-        int y = nif->getInt();
-        int offset = nif->getInt();
+        /*int x =*/ nif->getInt();
+        /*int y =*/ nif->getInt();
+        /*int offset =*/ nif->getInt();
       }
 
     // Skip the data
diff --git a/nif/extra.hpp b/nif/extra.hpp
index 64c512509..788fe3113 100644
--- a/nif/extra.hpp
+++ b/nif/extra.hpp
@@ -50,7 +50,7 @@ struct NiVertWeightsExtraData : Extra
 
     // We should have s*4+2 == i, for some reason. Might simply be the
     // size of the rest of the record, unhelpful as that may be.
-    int i = nif->getInt();
+    /*int i =*/ nif->getInt();
     int s = nif->getShort(); // number of vertices
 
     nif->getFloatLen(s);     // vertex weights I guess
diff --git a/nif/nif_file.cpp b/nif/nif_file.cpp
index 0decd77e1..dc7fc2ed8 100644
--- a/nif/nif_file.cpp
+++ b/nif/nif_file.cpp
@@ -178,7 +178,7 @@ void NIFFile::parse()
 void NiSkinInstance::post(NIFFile *nif)
 {
   int bnum = bones.length();
-  if(bnum != data->bones.size())
+  if(bnum != static_cast<int> (data->bones.size()))
     nif->fail("Mismatch in NiSkinData bone count");
 
   root->makeRootBone(data->trafo);
diff --git a/nif/nif_file.hpp b/nif/nif_file.hpp
index a827758d4..a1c34b3bb 100644
--- a/nif/nif_file.hpp
+++ b/nif/nif_file.hpp
@@ -95,7 +95,7 @@ class NIFFile
 
   ~NIFFile()
     {
-      for(int i=0; i<records.size(); i++)
+      for(std::size_t i=0; i<records.size(); i++)
         {
           delete records[i];
         }
@@ -104,7 +104,7 @@ class NIFFile
   /// Get a given record
   Record *getRecord(int index)
   {
-    assert(index >= 0 && index < records.size());
+    assert(index >= 0 && index < static_cast<int> (records.size()));
     Record *res = records[index];
     assert(res != NULL);
     return res;
diff --git a/nif/property.hpp b/nif/property.hpp
index c17bcfe62..3500a25b7 100644
--- a/nif/property.hpp
+++ b/nif/property.hpp
@@ -122,9 +122,9 @@ struct NiTexturingProperty : Property
     if(textures[5].inUse)
       {
         // Ignore these at the moment
-        float lumaScale = nif->getFloat();
-        float lumaOffset = nif->getFloat();
-        const Vector4 *lumaMatrix = nif->getVector4();
+        /*float lumaScale =*/ nif->getFloat();
+        /*float lumaOffset =*/ nif->getFloat();
+        /*const Vector4 *lumaMatrix =*/ nif->getVector4();
       }
     textures[6].read(nif); // Decal
   }
diff --git a/nif/record_ptr.hpp b/nif/record_ptr.hpp
index 3011aaa17..c5618941e 100644
--- a/nif/record_ptr.hpp
+++ b/nif/record_ptr.hpp
@@ -118,13 +118,13 @@ class RecordListT
 
   X& operator[](int index)
     {
-      assert(index >= 0 && index < list.size());
+      assert(index >= 0 && index < static_cast<int> (list.size()));
       return list[index].get();
     }
 
   bool has(int index)
   {
-    assert(index >= 0 && index < list.size());
+    assert(index >= 0 && index < static_cast<int> (list.size()));
     return !list[index].empty();
   }
 
diff --git a/nifogre/ogre_nif_loader.cpp b/nifogre/ogre_nif_loader.cpp
index de00b443f..ba88e86ae 100644
--- a/nifogre/ogre_nif_loader.cpp
+++ b/nifogre/ogre_nif_loader.cpp
@@ -193,7 +193,7 @@ static void createMaterial(const String &name,
   if(!texName.empty())
     {
       Pass *pass = material->getTechnique(0)->getPass(0);
-      TextureUnitState *txt = pass->createTextureUnitState(texName);
+      /*TextureUnitState *txt =*/ pass->createTextureUnitState(texName);
 
       /* As of yet UNTESTED code from Chris:
       pass->setTextureFiltering(Ogre::TFO_ANISOTROPIC);