diff --git a/Makefile b/Makefile
index 98151f7ea56..a2e5ae01008 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
 # $Header$
 
 CC      = gcc
-CFLAGS  = -g -Wno-multichar
+CFLAGS  = -g -Wall -Wstrict-prototypes -Wno-long-long -Wno-multichar 
 DEFINES = -DUNIX -DUSE_ADLIB 
 LDFLAGS :=
 INCLUDES:= `sdl-config --cflags` -I./ -I./sound
diff --git a/actor.cpp b/actor.cpp
index 7811345037f..fb29e174384 100644
--- a/actor.cpp
+++ b/actor.cpp
@@ -977,7 +977,7 @@ void Scumm::actorTalk() {
 
 	_msgPtrToAdd = charset._buffer;
 	_messagePtr = addMessageToStack(_messagePtr);
-	assert(_msgPtrToAdd - charset._buffer < sizeof(charset._buffer));
+	assert((int)(_msgPtrToAdd - charset._buffer) < (int)(sizeof(charset._buffer)));
 	
 	if (_actorToPrintStrFor==0xFF) {
 		if (!_keepText)
diff --git a/debug.cpp b/debug.cpp
index e22a33af536..2938fd405b8 100644
--- a/debug.cpp
+++ b/debug.cpp
@@ -110,7 +110,7 @@ bool ScummDebugger::do_command() {
 		return true;
 	case CMD_DUMPBOX:
 		{
-			int num, i = 0, rows = 0; 
+			int num, i = 0;
 			BoxCoords box;		
 			byte *boxm = _s->getBoxMatrixBaseAddr();
 			num = _s->getNumBoxes();			
@@ -206,11 +206,11 @@ static const DebuggerCommands debugger_commands[] = {
 	{ "a", 1, CMD_ACTOR },
 	{ "s", 1, CMD_SCRIPTS },
 	{ "r", 1, CMD_LOAD_ROOM },
-    { "b", 1, CMD_DUMPBOX},
+	{ "b", 1, CMD_DUMPBOX},
 	{ "v", 1, CMD_VAR},
 	{ "w", 1, CMD_WATCH},
 	{ "e", 1, CMD_EXIT },
-	{ 0, 0, 0 },
+	{ "" , 0, 0 }
 };
 
 int ScummDebugger::get_command() {
diff --git a/gfx.cpp b/gfx.cpp
index a80132c9495..b6b3d6ad19a 100644
--- a/gfx.cpp
+++ b/gfx.cpp
@@ -940,7 +940,7 @@ void Gdi::decompressMaskImgOr() {
 void Scumm::redrawBGStrip(int start, int num) {
 	int s = _screenStartStrip + start;
 
-	assert(s>=0 && s<sizeof(gfxUsageBits)/sizeof(gfxUsageBits[0]));
+	assert(s>=0 && (size_t)s<sizeof(gfxUsageBits)/sizeof(gfxUsageBits[0]));
 
 	_curVirtScreen = &virtscr[0];
 
diff --git a/gui.cpp b/gui.cpp
index 8adc342c54a..761546df748 100644
--- a/gui.cpp
+++ b/gui.cpp
@@ -33,7 +33,7 @@ void Gui::draw(int start,int end) {
 	if (end==-1)
 		end=start;
 
-	for (i=0; i<sizeof(_widgets) / sizeof(_widgets[0]); i++) {
+	for (i=0; i<(int)(sizeof(_widgets) / sizeof(_widgets[0])); i++) {
 		const GuiWidget *w = _widgets[i];
 		if (w) {
 			_parentX = 0;
diff --git a/insane.cpp b/insane.cpp
index 0f1fb0dda05..095714c0070 100644
--- a/insane.cpp
+++ b/insane.cpp
@@ -594,7 +594,7 @@ void codec37_maketable(PersistentCodecData37 *pcd, int pitch, byte idx) {
 
 
 
-	assert(idx*255 + 254 < sizeof(maketable_bytes)/2);
+	assert(idx*255 + 254 < (int)(sizeof(maketable_bytes)/2));
 
 
 
@@ -618,7 +618,7 @@ void codec37(CodecData *cd, PersistentCodecData37 *pcd) {
 
 	int src_pitch;
 
-	byte *src = cd->src, *curbuf;
+	byte *curbuf;
 
 	uint size;
 
diff --git a/object.cpp b/object.cpp
index 08f717bf18a..df857cbb6bc 100644
--- a/object.cpp
+++ b/object.cpp
@@ -654,7 +654,7 @@ void Scumm::removeObjectFromRoom(int obj) {
 
 void Scumm::addObjectToDrawQue(int object) {
 	_drawObjectQue[_drawObjectQueNr++] = object;
-	if (_drawObjectQueNr > sizeof(_drawObjectQue)/sizeof(_drawObjectQue[0]))
+	if ((unsigned int)_drawObjectQueNr > sizeof(_drawObjectQue)/sizeof(_drawObjectQue[0]))
 		error("Draw Object Que overflow");
 }
 
diff --git a/resource.cpp b/resource.cpp
index 9a2b806fe68..4edc81158a5 100644
--- a/resource.cpp
+++ b/resource.cpp
@@ -55,7 +55,7 @@ void Scumm::openRoom(int room) {
                         room_offs = room ? _roomFileOffsets[room] : 0;
 #endif
 		
-		if (room_offs == 0xFFFFFFFF)
+		if (room_offs == (int)0xFFFFFFFF)
 			break;
 
 		if (room_offs != 0 && room != 0) {
@@ -495,7 +495,7 @@ void Scumm::readResTypeList(int id, uint32 tag, const char *name) {
 
 void Scumm::allocResTypeData(int id, uint32 tag, int num, const char *name, int mode) {
 	debug(9, "allocResTypeData(%d,%x,%d,%s,%d)",id,FROM_LE_32(tag),num,name,mode);
-	assert(id>=0 && id<sizeof(res.mode)/sizeof(res.mode[0]));
+	assert(id>=0 && id<(int)(sizeof(res.mode)/sizeof(res.mode[0])));
 
 	if (num>=2000) {
 		error("Too many %ss (%d) in directory", name, num);
@@ -1099,7 +1099,7 @@ void Scumm::resourceStats() {
 			}
 		}
 	
-	printf("Total allocated size=%d, locked=%d(%d)\n", _allocatedSize, lockedSize, lockedNum);
+	printf("Total allocated size=%ld, locked=%ld(%ld)\n", _allocatedSize, lockedSize, lockedNum);
 }
 
 void Scumm::heapClear(int mode) {
diff --git a/script.cpp b/script.cpp
index d50adc95664..9d5a8b2ef82 100644
--- a/script.cpp
+++ b/script.cpp
@@ -732,12 +732,12 @@ int Scumm::getVerbEntrypoint(int obj, int entry) {
 
 
 void Scumm::push(int a) {
-	assert(_scummStackPos >=0 && _scummStackPos <= ARRAYSIZE(_scummStack));
+	assert(_scummStackPos >=0 && (unsigned int)_scummStackPos <= ARRAYSIZE(_scummStack));
 	_scummStack[_scummStackPos++] = a;	
 }
 
 int Scumm::pop() {
-	assert(_scummStackPos >0 && _scummStackPos <= ARRAYSIZE(_scummStack));
+	assert(_scummStackPos >0 && (unsigned int)_scummStackPos <= ARRAYSIZE(_scummStack));
 	return _scummStack[--_scummStackPos];
 }
 
diff --git a/script_v1.cpp b/script_v1.cpp
index b881cca4cbc..fefc32dc578 100644
--- a/script_v1.cpp
+++ b/script_v1.cpp
@@ -1035,7 +1035,7 @@ void Scumm::o5_drawObject() {
 
         if (_features & GF_SMALL_HEADER) {
                 int temp = getVarOrDirectWord(0x40);
-                int room = getVarOrDirectWord(0x20);
+                getVarOrDirectWord(0x20);	// Room
  
                 idx = getObjectIndex(obj);
                 if(idx==-1)
@@ -1850,7 +1850,7 @@ void Scumm::o5_roomOps() {
 		char buf[256],*s;
 		a = getVarOrDirectByte(0x80);
 		s = buf;
-		while (*s++=fetchScriptByte());
+		while ((*s++=fetchScriptByte()));
 		warning("roomops:13 save-string(%d,\"%s\") not implemented", a, buf);
 		break;
 		}
@@ -1858,7 +1858,7 @@ void Scumm::o5_roomOps() {
 		char buf[256],*s;
 		a = getVarOrDirectByte(0x80);
 		s = buf;
-		while (*s++=fetchScriptByte());
+		while ((*s++=fetchScriptByte()));
 		warning("roomops:14 load-string(%d,\"%s\") not implemented", a, buf);
 		break;
 	case 15: /* palmanip? */
@@ -2364,7 +2364,8 @@ void Scumm::o5_walkActorToObject() {
 
 int Scumm::getWordVararg(int16 *ptr) {
 	int i;
-	for (i=0; i<16; i++)
+
+	for (i=0; i<15; i++)
 		ptr[i] = 0;
 
 	i = 0;
diff --git a/scumm.h b/scumm.h
index 555461ae01e..715a815b720 100644
--- a/scumm.h
+++ b/scumm.h
@@ -99,8 +99,10 @@ struct MemBlkHeader {
 };
 
 
-#pragma START_PACK_STRUCTS
-	
+#if !defined(__GNUC__)
+	#pragma START_PACK_STRUCTS
+#endif	
+
 #define SIZEOF_BOX 20
 struct Box { /* file format */
 	int16 ulx,uly;
@@ -219,7 +221,10 @@ struct ImageHeader { /* file format */
 		} GCC_PACK v7;
 	} GCC_PACK;
 } GCC_PACK;
-#pragma END_PACK_STRUCTS
+
+#if !defined(__GNUC__)
+	#pragma END_PACK_STRUCTS
+#endif
 
 struct AdjustBoxResult {
 	int16 x,y;
@@ -361,7 +366,7 @@ enum ResTypes {
 	rtBox = 15,
 	rtObjectName = 16,
 	rtLast = 16,
-	rtNumTypes = 17,
+	rtNumTypes = 17
 };
 
 enum {
@@ -375,7 +380,7 @@ enum {
 enum {
 	CM_NORMAL = 1,
 	CM_FOLLOW_ACTOR = 2,
-	CM_PANNING = 3,
+	CM_PANNING = 3
 };
 
 enum {
@@ -395,7 +400,7 @@ enum MoveFlags {
 	MF_NEW_LEG = 1,
 	MF_IN_LEG = 2,
 	MF_TURN = 4,
-	MF_LAST_LEG = 8,
+	MF_LAST_LEG = 8
 };
 
 #define _maxRooms res.num[rtRoom]
@@ -745,7 +750,7 @@ struct Gdi {
 	enum DrawBitmapFlags {
 		dbAllowMaskOr = 1,
 		dbDrawMaskOnBoth = 2,
-		dbClear = 4,
+		dbClear = 4
 	};
 };
 
@@ -792,7 +797,7 @@ enum GameId {
 	GID_INDY3_256 = 9,
 	GID_LOOM = 10,
 	GID_FT = 11,
-	GID_DIG = 12,
+	GID_DIG = 12
 };
 
 enum GameFeatures {
@@ -814,7 +819,7 @@ enum GameFeatures {
 	GF_16COLOR = 256,
 	GF_OLD256 = 512,
 	GF_AUDIOTRACKS = 1024,
-	GF_NO_SCALLING = 2048,
+	GF_NO_SCALLING = 2048
 };
 
 struct ScummDebugger;
@@ -1941,7 +1946,7 @@ struct Scumm {
 	enum FindObjectWhat {
 		foCodeHeader = 1,
 		foImageHeader = 2,
-		foCheckAlreadyLoaded = 4,
+		foCheckAlreadyLoaded = 4
 	};
 
 	void findObjectInRoom(FindObjectInRoom *fo, byte findWhat, uint object, uint room);
@@ -2170,7 +2175,7 @@ enum AkosOpcodes{
 	AKC_JumpLE  = 0xC093,
 	AKC_JumpG  = 0xC094,
 	AKC_JumpGE  = 0xC095,
-	AKC_ClearFlag  = 0xC09F,
+	AKC_ClearFlag  = 0xC09F
 };
 
 
diff --git a/scummsys.h b/scummsys.h
index da2ae4fed9e..6a4b5f9ef19 100644
--- a/scummsys.h
+++ b/scummsys.h
@@ -236,31 +236,31 @@ typedef signed long int32;
 #define MKID(a) ((((a)>>24)&0xFF) | (((a)>>8)&0xFF00) | (((a)<<8)&0xFF0000) | (((a)<<24)&0xFF000000))
 
 #if defined(SCUMM_NEED_ALIGNMENT)
-	uint FORCEINLINE READ_LE_UINT16(void *ptr) {
+	FORCEINLINE uint READ_LE_UINT16(void *ptr) {
 		return (((byte*)ptr)[1]<<8)|((byte*)ptr)[0];
 	}
 #else
-	uint FORCEINLINE READ_LE_UINT16(void *ptr) {
+	FORCEINLINE uint READ_LE_UINT16(void *ptr) {
 		return *(uint16*)(ptr);
 	}
 #endif
 
-uint FORCEINLINE READ_BE_UINT16(void *ptr) {
+FORCEINLINE uint READ_BE_UINT16(void *ptr) {
 	return (((byte*)ptr)[0]<<8)|((byte*)ptr)[1];
 }
 
 #if defined(SCUMM_NEED_ALIGNMENT)
-	uint32 FORCEINLINE READ_LE_UINT32(void *ptr) {
+	FORCEINLINE uint32 READ_LE_UINT32(void *ptr) {
 		byte *b = (byte*)ptr;
 		return (b[3]<<24)+(b[2]<<16)+(b[1]<<8)+(b[0]);
 	}
 #else
-	uint32 FORCEINLINE READ_LE_UINT32(void *ptr) {
+	FORCEINLINE uint32 READ_LE_UINT32(void *ptr) {
 		return *(uint32*)(ptr);
 	}
 #endif
 
-uint32 FORCEINLINE READ_BE_UINT32(void *ptr) {
+FORCEINLINE uint32 READ_BE_UINT32(void *ptr) {
 	byte *b = (byte*)ptr;
 	return (b[0]<<24)+(b[1]<<16)+(b[2]<<8)+(b[3]);
 }
diff --git a/scummvm.cpp b/scummvm.cpp
index 48ab2a882aa..69d4acdfb0b 100644
--- a/scummvm.cpp
+++ b/scummvm.cpp
@@ -855,7 +855,7 @@ void Scumm::initRoomSubBlocks() {
 	searchptr = roomptr = getResourceAddress(rtRoom, _roomResource);
 	if(_features & GF_SMALL_HEADER) {
 		while( (ptr = findResourceSmall(MKID('LSCR'), searchptr)) != NULL ) {
-			int id;
+			int id = 0;
 			ptr += _resourceHeaderSize; /* skip tag & size */
 	#ifdef DUMP_SCRIPTS
 			do {
@@ -870,7 +870,7 @@ void Scumm::initRoomSubBlocks() {
 		}
 	} else {
                 while( (ptr = findResource(MKID('LSCR'), searchptr)) != NULL ) {
-                        int id;
+                        int id = 0;
 
                         ptr += _resourceHeaderSize; /* skip tag & size */
                         
diff --git a/sdl.cpp b/sdl.cpp
index 8723812e1ee..594d1bc768d 100644
--- a/sdl.cpp
+++ b/sdl.cpp
@@ -658,8 +658,6 @@ void drawMouse(Scumm *s, int xdraw, int ydraw, int w, int h, byte *buf, bool vis
 	}
 }
 
-static uint32 midi_counter;
-
 void fill_sound(void *userdata, Uint8 *stream, int len) {
 	scumm.mixWaves((int16*)stream, len>>1);
 }
diff --git a/sys.cpp b/sys.cpp
index 044e80d3404..cbcf059ea2f 100644
--- a/sys.cpp
+++ b/sys.cpp
@@ -51,7 +51,6 @@ void Scumm::clearFileReadFailed(void *file) {
 }
 
 bool Scumm::fileEof(void *file) {
-	FILE *a = (FILE*)file;
 	return feof((FILE*)file) != 0;
 }
 
diff --git a/windows.cpp b/windows.cpp
index 7890054c27e..5d43000ce4f 100644
--- a/windows.cpp
+++ b/windows.cpp
@@ -507,9 +507,9 @@ DWORD _stdcall WndMan::sound_thread(WndMan *wm) {
 	int time = GetTickCount(), cur;
 
 	while (1) {
+		cur = GetTickCount();
 
 		if (!snd_driv.wave_based()) {
-			cur = GetTickCount();
 			while (time < cur) {
 				sound.on_timer();
 				time += 10;