diff --git a/src/GameState.cpp b/src/GameState.cpp
index 11365834ea..0daead14cf 100644
--- a/src/GameState.cpp
+++ b/src/GameState.cpp
@@ -1551,6 +1551,8 @@ bool GameState::ShowW1() const
 	case ALLOW_W1_EVERYWHERE:	return true;
 	default:	ASSERT(0);
 	}
+	// it should never hit here.
+	return false;
 }
 
 
@@ -2424,7 +2426,7 @@ public:
 		LuaHelpers::CreateTableFromArray( vHP, L );
 		return 1;
 	}
-  static int GetEnabledPlayers(T* p, lua_State *L )
+  static int GetEnabledPlayers(T* , lua_State *L )
   {
     vector<PlayerNumber> vEP;
     FOREACH_EnabledPlayer( pn )
@@ -2438,7 +2440,7 @@ public:
 		LuaHelpers::Push( L, pStyle );
 		return 1;
 	}
-	static int IsAnyHumanPlayerUsingMemoryCard( T* p, lua_State *L )
+	static int IsAnyHumanPlayerUsingMemoryCard( T* , lua_State *L )
 	{
 		bool bUsingMemoryCard = false;
 		FOREACH_HumanPlayer( pn )
@@ -2449,7 +2451,11 @@ public:
 		lua_pushboolean(L, bUsingMemoryCard );
 		return 1;
 	}
-	static int GetNumStagesForCurrentSongAndStepsOrCourse( T* p, lua_State *L ) { lua_pushnumber(L, GAMESTATE->GetNumStagesForCurrentSongAndStepsOrCourse() ); return 1; }
+	static int GetNumStagesForCurrentSongAndStepsOrCourse( T* , lua_State *L )
+	{ 
+		lua_pushnumber(L, GAMESTATE->GetNumStagesForCurrentSongAndStepsOrCourse() );
+		return 1; 
+	}
 	static int GetNumStagesLeft( T* p, lua_State *L )
 	{
 		PlayerNumber pn = Enum::Check<PlayerNumber>(L, 1);
diff --git a/src/ProfileManager.cpp b/src/ProfileManager.cpp
index 9c56d5af6b..6b154fb0fc 100644
--- a/src/ProfileManager.cpp
+++ b/src/ProfileManager.cpp
@@ -580,8 +580,10 @@ const RString& ProfileManager::GetProfileDir( ProfileSlot slot ) const
 	case ProfileSlot_Machine:
 		return MACHINE_PROFILE_DIR;
 	default:
-		ASSERT(0);
+		break;
 	}
+	// it should never hit here.
+	FAIL_M("Invalid profile slot chosen: unable to get the directory!");
 }
 
 RString ProfileManager::GetProfileDirImportedFrom( ProfileSlot slot ) const
@@ -596,6 +598,8 @@ RString ProfileManager::GetProfileDirImportedFrom( ProfileSlot slot ) const
 	default:
 		ASSERT(0);
 	}
+	// it should never hit here.
+	return RString();
 }
 
 const Profile* ProfileManager::GetProfile( ProfileSlot slot ) const
@@ -610,6 +614,8 @@ const Profile* ProfileManager::GetProfile( ProfileSlot slot ) const
 	default:
 		ASSERT(0);
 	}
+	// it should never hit here.
+	return NULL;
 }
 
 //
@@ -822,7 +828,7 @@ public:
 	static int IsPersistentProfile( T* p, lua_State *L )	{ lua_pushboolean(L, p->IsPersistentProfile(Enum::Check<PlayerNumber>(L, 1)) ); return 1; }
 	static int GetProfile( T* p, lua_State *L )				{ PlayerNumber pn = Enum::Check<PlayerNumber>(L, 1); Profile* pP = p->GetProfile(pn); ASSERT(pP != NULL); pP->PushSelf(L); return 1; }
 	static int GetMachineProfile( T* p, lua_State *L )		{ p->GetMachineProfile()->PushSelf(L); return 1; }
-	static int SaveMachineProfile( T* p, lua_State *L )		{ p->SaveMachineProfile(); return 0; }
+	static int SaveMachineProfile( T* p, lua_State * )		{ p->SaveMachineProfile(); return 0; }
 	static int GetLocalProfile( T* p, lua_State *L )
 	{
 		Profile *pProfile = p->GetLocalProfile(SArg(1));
@@ -842,7 +848,7 @@ public:
 	static int LastLoadWasTamperedOrCorrupt( T* p, lua_State *L ) { lua_pushboolean(L, p->LastLoadWasTamperedOrCorrupt(Enum::Check<PlayerNumber>(L, 1)) ); return 1; }
 	static int GetPlayerName( T* p, lua_State *L )				{ PlayerNumber pn = Enum::Check<PlayerNumber>(L, 1); lua_pushstring(L, p->GetPlayerName(pn)); return 1; }
 
-	static int LocalProfileIDToDir( T* p, lua_State *L )
+	static int LocalProfileIDToDir( T* , lua_State *L )
 	{
 		RString dir = USER_PROFILES_DIR + SArg(1) + "/";
 		lua_pushstring( L, dir );
diff --git a/src/RageDisplay_D3D.cpp b/src/RageDisplay_D3D.cpp
index 1f387e7c29..351e8bedb3 100644
--- a/src/RageDisplay_D3D.cpp
+++ b/src/RageDisplay_D3D.cpp
@@ -185,7 +185,7 @@ static LocalizedString D3D_NOT_INSTALLED ( "RageDisplay_D3D", "DirectX 8.1 or gr
 const RString D3D_URL = "http://www.microsoft.com/downloads/details.aspx?FamilyID=a19bed22-0b25-4e5d-a584-6389d8a3dad0&displaylang=en";
 static LocalizedString HARDWARE_ACCELERATION_NOT_AVAILABLE ( "RageDisplay_D3D", 
 	"Your system is reporting that Direct3D hardware acceleration is not available.  Please obtain an updated driver from your video card manufacturer." );
-RString RageDisplay_D3D::Init( const VideoModeParams &p, bool bAllowUnacceleratedRenderer )
+RString RageDisplay_D3D::Init( const VideoModeParams &p, bool /* bAllowUnacceleratedRenderer */ )
 {
 	GraphicsWindow::Initialize( true );
 
@@ -661,7 +661,7 @@ RageSurface* RageDisplay_D3D::CreateScreenshot()
 	}
 
 	RageSurface *surface = CreateSurfaceFromPixfmt( PixelFormat_RGBA8, lr.pBits, desc.Width, desc.Height, lr.Pitch);
-	ASSERT( surface );
+	ASSERT( surface != NULL );
 
 	// We need to make a copy, since lr.pBits will go away when we call UnlockRect().
 	RageSurface *SurfaceCopy = 
@@ -1406,7 +1406,7 @@ void RageDisplay_D3D::UpdateTexture(
 	ASSERT( texpixfmt != NUM_PixelFormat );
 
 	RageSurface *Texture = CreateSurfaceFromPixfmt(PixelFormat(texpixfmt), lr.pBits, width, height, lr.Pitch);
-	ASSERT( Texture );
+	ASSERT( Texture != NULL );
 	RageSurfaceUtils::Blit( img, Texture, width, height );
 
 	delete Texture;
diff --git a/src/RageSound.cpp b/src/RageSound.cpp
index f53ce1c0a5..462be50b15 100644
--- a/src/RageSound.cpp
+++ b/src/RageSound.cpp
@@ -53,7 +53,7 @@ RageSound::RageSound():
 	m_iStoppedSourceFrame(0), m_bPlaying(false),
 	m_bDeleteWhenFinished(false), m_sError("")
 {
-	ASSERT( SOUNDMAN );
+	ASSERT( SOUNDMAN != NULL );
 }
 
 RageSound::~RageSound()
@@ -65,7 +65,7 @@ RageSound::RageSound( const RageSound &cpy ):
 	RageSoundBase( cpy ),
 	m_Mutex( "RageSound" )
 {
-	ASSERT(SOUNDMAN);
+	ASSERT(SOUNDMAN != NULL);
 
 	m_pSource = NULL;
 
@@ -266,7 +266,7 @@ int RageSound::GetDataToPlay( float *pBuffer, int iFrames, int64_t &iStreamFrame
 //	LockMut(m_Mutex);
 
 	ASSERT_M( m_bPlaying, ssprintf("%p", this) );
-	ASSERT( m_pSource );
+	ASSERT( m_pSource != NULL );
 
 	iFramesStored = 0;
 	iStreamFrame = m_iStreamFrame;
diff --git a/src/RageSoundReader.h b/src/RageSoundReader.h
index ccb99351cd..635f4fefc0 100644
--- a/src/RageSoundReader.h
+++ b/src/RageSoundReader.h
@@ -14,7 +14,7 @@ public:
 	virtual RageSoundReader *Copy() const = 0;
 	virtual int GetSampleRate() const = 0;
 	virtual unsigned GetNumChannels() const = 0;
-	virtual bool SetProperty( const RString &sProperty, float fValue ) { return false; }
+	virtual bool SetProperty( const RString & /* sProperty */, float /* fValue */ ) { return false; }
 	virtual RageSoundReader *GetSource() { return NULL; }
 
 	/* Return values for Read(). */
diff --git a/src/RageSoundReader_Extend.cpp b/src/RageSoundReader_Extend.cpp
index 38beacfa35..c5e5e87f1c 100644
--- a/src/RageSoundReader_Extend.cpp
+++ b/src/RageSoundReader_Extend.cpp
@@ -15,7 +15,7 @@
 RageSoundReader_Extend::RageSoundReader_Extend( RageSoundReader *pSource ):
 	RageSoundReader_Filter( pSource )
 {
-	ASSERT_M(pSource, "The music file was not found! Was it deleted or moved while the game was on?");
+	ASSERT_M(pSource != NULL, "The music file was not found! Was it deleted or moved while the game was on?");
 	m_iPositionFrames = pSource->GetNextSourceFrame();
 
 	m_StopMode = M_STOP;
diff --git a/src/RageSoundReader_Preload.cpp b/src/RageSoundReader_Preload.cpp
index c0a2253dd1..ff7e659bf1 100644
--- a/src/RageSoundReader_Preload.cpp
+++ b/src/RageSoundReader_Preload.cpp
@@ -47,7 +47,7 @@ int RageSoundReader_Preload::GetTotalFrames() const
 
 bool RageSoundReader_Preload::Open( RageSoundReader *pSource )
 {
-	ASSERT( pSource );
+	ASSERT( pSource != NULL );
 	m_iSampleRate = pSource->GetSampleRate();
 	m_iChannels = pSource->GetNumChannels();
 	m_fRate = pSource->GetStreamToSourceRatio();
diff --git a/src/RageSoundReader_Resample_Good.cpp b/src/RageSoundReader_Resample_Good.cpp
index 9721dd6cc7..ecc176c108 100644
--- a/src/RageSoundReader_Resample_Good.cpp
+++ b/src/RageSoundReader_Resample_Good.cpp
@@ -667,7 +667,7 @@ int RageSoundReader_Resample_Good::Read( float *pBuf, int iFrames )
 	{
 		int iFramesNeeded = m_apResamplers[0]->NumInputsForOutputSamples(iFrames);
 		float *pTmpBuf = (float *) alloca( iFramesNeeded * sizeof(float) * iChannels );
-		ASSERT( pTmpBuf );
+		ASSERT( pTmpBuf != NULL );
 		int iFramesIn = m_pSource->Read( pTmpBuf, iFramesNeeded );
 		if( iFramesIn < 0 )
 			return iFramesIn;
diff --git a/src/RageSoundReader_Vorbisfile.cpp b/src/RageSoundReader_Vorbisfile.cpp
index 3f040f4e31..6b60ab34bc 100644
--- a/src/RageSoundReader_Vorbisfile.cpp
+++ b/src/RageSoundReader_Vorbisfile.cpp
@@ -261,7 +261,7 @@ int RageSoundReader_Vorbisfile::Read( float *buf, int iFrames )
 
 int RageSoundReader_Vorbisfile::GetSampleRate() const
 {
-	ASSERT(vf);
+	ASSERT(vf != NULL);
 
 	vorbis_info *vi = ov_info(vf, -1);
 	ASSERT(vi != NULL);
@@ -271,7 +271,7 @@ int RageSoundReader_Vorbisfile::GetSampleRate() const
 
 int RageSoundReader_Vorbisfile::GetNextSourceFrame() const
 {
-	ASSERT(vf);
+	ASSERT(vf != NULL);
 
 	int iFrame = (int)ov_pcm_tell( vf );
 	return iFrame;
diff --git a/src/RageTimer.cpp b/src/RageTimer.cpp
index 8b15b3341b..3c480dc7af 100644
--- a/src/RageTimer.cpp
+++ b/src/RageTimer.cpp
@@ -32,7 +32,7 @@
 const RageTimer RageZeroTimer(0,0);
 static uint64_t g_iStartTime = ArchHooks::GetMicrosecondsSinceStart( true );
 
-static uint64_t GetTime( bool bAccurate )
+static uint64_t GetTime( bool /* bAccurate */ )
 {
 	return ArchHooks::GetMicrosecondsSinceStart( true );
 
diff --git a/src/ScreenGameplay.h b/src/ScreenGameplay.h
index fee3d0d97d..2027870be6 100644
--- a/src/ScreenGameplay.h
+++ b/src/ScreenGameplay.h
@@ -172,7 +172,7 @@ public:
 	bool IsPaused() const { return m_bPaused; }
 
 protected:
-	virtual void UpdateStageStats( MultiPlayer mp ) {};	// overridden for multiplayer
+	virtual void UpdateStageStats( MultiPlayer /* mp */ ) {};	// overridden for multiplayer
 
 	virtual bool UseSongBackgroundAndForeground() const { return true; }
 
diff --git a/src/XmlFile.cpp b/src/XmlFile.cpp
index 7e99ecb41e..1cb67627d8 100644
--- a/src/XmlFile.cpp
+++ b/src/XmlFile.cpp
@@ -137,7 +137,7 @@ XNode *XNode::AppendChild( XNode *node )
 }
 
 // detach node and delete object
-bool XNode::RemoveChild( XNode *node, bool bDelete )
+bool XNode::RemoveChild( XNode *node, bool /* bDelete */ )
 {
 	XNodes::iterator it = find( m_childs.begin(), m_childs.end(), node );
 	if( it == m_childs.end() )
diff --git a/src/archutils/Win32/MessageWindow.h b/src/archutils/Win32/MessageWindow.h
index 50da20d92e..093adebfe9 100644
--- a/src/archutils/Win32/MessageWindow.h
+++ b/src/archutils/Win32/MessageWindow.h
@@ -17,7 +17,7 @@ public:
 	HWND GetHwnd() { return m_hWnd; }
 
 protected:
-	virtual bool HandleMessage( UINT msg, WPARAM wParam, LPARAM lParam ) { return false; }
+	virtual bool HandleMessage( UINT /* msg */, WPARAM /* wParam */, LPARAM /* lParam */ ) { return false; }
 	void StopRunning();
 
 private:
diff --git a/src/archutils/Win32/arch_setup.cpp b/src/archutils/Win32/arch_setup.cpp
index b2182733be..7175e9a66c 100644
--- a/src/archutils/Win32/arch_setup.cpp
+++ b/src/archutils/Win32/arch_setup.cpp
@@ -7,7 +7,7 @@
 
 #if defined(WINDOWS)
 int main( int argc, char* argv[] );
-int __stdcall WinMain( HINSTANCE hInstance, HINSTANCE hPrevInstance, char *pCmdLine, int nCmdShow )
+int __stdcall WinMain( HINSTANCE /* hInstance */, HINSTANCE  /* hPrevInstance */, char * /* pCmdLine */, int /* nCmdShow */ )
 {
 	char **argv;
 	int argc = GetWin32CmdLine( argv );