diff --git a/source/audiolib/src/driver_directsound.cpp b/source/audiolib/src/driver_directsound.cpp
index b1a5fc56c..a84194f4f 100644
--- a/source/audiolib/src/driver_directsound.cpp
+++ b/source/audiolib/src/driver_directsound.cpp
@@ -26,8 +26,7 @@
 #define NEED_DSOUND_H
 #include "windows_inc.h"
 
-#include <stdlib.h>
-#include <stdio.h>
+#include "compat.h"
 
 #include "driver_directsound.h"
 #include "multivoc.h"
diff --git a/source/audiolib/src/driver_sdl.cpp b/source/audiolib/src/driver_sdl.cpp
index f8e0e3a82..541330806 100644
--- a/source/audiolib/src/driver_sdl.cpp
+++ b/source/audiolib/src/driver_sdl.cpp
@@ -22,7 +22,6 @@
  * libSDL output driver for MultiVoc
  */
 
-#include <string.h>
 #define _NEED_SDLMIXER
 #include "compat.h"
 #include "sdl_inc.h"
diff --git a/source/audiolib/src/flac.cpp b/source/audiolib/src/flac.cpp
index 75ede1b45..0521485f1 100644
--- a/source/audiolib/src/flac.cpp
+++ b/source/audiolib/src/flac.cpp
@@ -22,6 +22,8 @@
  * FLAC source support for MultiVoc
  */
 
+#include "compat.h"
+
 #ifdef HAVE_FLAC
 
 #define FLAC__NO_DLL
@@ -32,13 +34,6 @@
 #include "FLAC/all.h"
 #endif
 
-#include <stdlib.h>
-#include <stdio.h>
-#include <string.h>
-#ifndef _MSC_VER
-#include <unistd.h>
-#endif
-#include <errno.h>
 #include "pitch.h"
 #include "multivoc.h"
 #include "_multivc.h"
@@ -669,8 +664,6 @@ void MV_ReleaseFLACVoice(VoiceNode *voice)
     voice->rawdataptr = 0;
 }
 #else
-#include <stdlib.h>
-#include <stdio.h>
 #include "_multivc.h"
 
 int32_t MV_PlayFLAC(char *ptr, uint32_t ptrlength, int32_t loopstart, int32_t loopend, int32_t pitchoffset,
diff --git a/source/audiolib/src/formats.cpp b/source/audiolib/src/formats.cpp
index a71cc5038..82705a4b6 100644
--- a/source/audiolib/src/formats.cpp
+++ b/source/audiolib/src/formats.cpp
@@ -24,13 +24,7 @@
  * Raw, WAV, and VOC source support for MultiVoc
  */
 
-#include <stdlib.h>
-#include <stdio.h>
-#include <string.h>
-#ifndef _MSC_VER
-#include <unistd.h>
-#endif
-#include <errno.h>
+#include "compat.h"
 #include "pitch.h"
 #include "multivoc.h"
 #include "_multivc.h"
diff --git a/source/audiolib/src/fx_man.cpp b/source/audiolib/src/fx_man.cpp
index 2bbfd9c5d..1c9fd2db1 100644
--- a/source/audiolib/src/fx_man.cpp
+++ b/source/audiolib/src/fx_man.cpp
@@ -21,9 +21,6 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 //-------------------------------------------------------------------------
 
 #include "compat.h"
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
 #include "drivers.h"
 #include "multivoc.h"
 #include "fx_man.h"
diff --git a/source/audiolib/src/multivoc.cpp b/source/audiolib/src/multivoc.cpp
index 0a21ed866..8f9c6b3fa 100644
--- a/source/audiolib/src/multivoc.cpp
+++ b/source/audiolib/src/multivoc.cpp
@@ -33,11 +33,6 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 
 #include "compat.h"
 #include "pragmas.h"
-#include <stdlib.h>
-#include <stdint.h>
-#include <string.h>
-#include <time.h>
-#include <stdio.h>
 #include "linklist.h"
 #include "drivers.h"
 #include "pitch.h"
diff --git a/source/audiolib/src/pitch.cpp b/source/audiolib/src/pitch.cpp
index 7cdb63fc6..c792dce42 100644
--- a/source/audiolib/src/pitch.cpp
+++ b/source/audiolib/src/pitch.cpp
@@ -28,8 +28,7 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
    (c) Copyright 1993 James R. Dose.  All Rights Reserved.
 **********************************************************************/
 
-#include <stdlib.h>
-#include <math.h>
+#include "compat.h"
 #include "pitch.h"
 
 #define MAXDETUNE 50
diff --git a/source/audiolib/src/vorbis.cpp b/source/audiolib/src/vorbis.cpp
index 6c5bfb240..28bc0bb4b 100644
--- a/source/audiolib/src/vorbis.cpp
+++ b/source/audiolib/src/vorbis.cpp
@@ -22,15 +22,10 @@
  * OggVorbis source support for MultiVoc
  */
 
+#include "compat.h"
+
 #ifdef HAVE_VORBIS
 
-#include <stdlib.h>
-#include <stdio.h>
-#include <string.h>
-#ifndef _MSC_VER
-#include <unistd.h>
-#endif
-#include <errno.h>
 #include "pitch.h"
 #include "multivoc.h"
 #include "_multivc.h"
@@ -483,8 +478,6 @@ void MV_ReleaseVorbisVoice( VoiceNode * voice )
     voice->rawdataptr = 0;
 }
 #else
-#include <stdlib.h>
-#include <stdio.h>
 #include "_multivc.h"
 
 int32_t MV_PlayVorbis(char *ptr, uint32_t ptrlength, int32_t loopstart, int32_t loopend, int32_t pitchoffset,
diff --git a/source/audiolib/src/xa.cpp b/source/audiolib/src/xa.cpp
index 198df09a0..6e5f5f5d6 100644
--- a/source/audiolib/src/xa.cpp
+++ b/source/audiolib/src/xa.cpp
@@ -4,11 +4,7 @@
  * Adapted and remixed from superxa2wav
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <math.h>
-#include <stdint.h>
+#include "compat.h"
 #include "pitch.h"
 #include "multivoc.h"
 #include "_multivc.h"
diff --git a/source/audiolib/src/xmp.cpp b/source/audiolib/src/xmp.cpp
index 371146a3b..fe630d050 100644
--- a/source/audiolib/src/xmp.cpp
+++ b/source/audiolib/src/xmp.cpp
@@ -1,8 +1,5 @@
 
-#include <stdlib.h>
-#include <stdio.h>
-#include <string.h>
-#include <ctype.h>
+#include "compat.h"
 
 #ifdef HAVE_XMP
 
diff --git a/source/build/include/a.h b/source/build/include/a.h
index 4580894fb..b8c86d2c2 100644
--- a/source/build/include/a.h
+++ b/source/build/include/a.h
@@ -91,7 +91,6 @@ extern void __cdecl stretchhline(int32_t,int32_t,int32_t,int32_t,int32_t,int32_t
 #else // !defined(NOASM) && (defined(_MSC_VER) || (defined(__GNUC__) && defined(__i386__)))
 
 #define ENGINE_USING_A_C
-#include <stdint.h>
 
 #define prevlineasm1 vlineasm1
 
diff --git a/source/build/include/compat.h b/source/build/include/compat.h
index 603a45e59..1faf4783a 100644
--- a/source/build/include/compat.h
+++ b/source/build/include/compat.h
@@ -301,6 +301,7 @@ defined __x86_64__ || defined __amd64__ || defined _M_X64 || defined _M_IA64 ||
 # include "msvc/inttypes.h" // from http://code.google.com/p/msinttypes/
 #endif
 
+#include <limits.h>
 #include <stddef.h>
 #include <stdarg.h>
 #include <stdlib.h>
@@ -308,6 +309,7 @@ defined __x86_64__ || defined __amd64__ || defined _M_X64 || defined _M_IA64 ||
 #include <string.h>
 
 #include <math.h>
+#include <float.h>
 
 #include <time.h>
 #include <ctype.h>
@@ -328,14 +330,11 @@ defined __x86_64__ || defined __amd64__ || defined _M_X64 || defined _M_IA64 ||
 
 #if defined(_WIN32)
 # include <io.h>
+# include <direct.h>
 #else
 # include <unistd.h>
 #endif
 
-#ifdef _MSC_VER
-# include <direct.h>
-#endif
-
 
 ////////// External library headers //////////
 
diff --git a/source/build/include/editor.h b/source/build/include/editor.h
index fe2dacebb..af6f76a3f 100644
--- a/source/build/include/editor.h
+++ b/source/build/include/editor.h
@@ -5,8 +5,8 @@
 #ifndef editor_h_
 #define editor_h_
 
+#include "compat.h"
 #include "baselayer.h"
-#include <math.h>
 
 #ifdef __cplusplus
 extern "C" {
diff --git a/source/build/include/pragmas.h b/source/build/include/pragmas.h
index b646f5e27..a2e9f2b66 100644
--- a/source/build/include/pragmas.h
+++ b/source/build/include/pragmas.h
@@ -9,8 +9,6 @@
 extern "C" {
 #endif
 
-#include <limits.h>
-
 #define EDUKE32_GENERATE_PRAGMAS                                                                                       \
     EDUKE32_SCALER_PRAGMA(1) EDUKE32_SCALER_PRAGMA(2) EDUKE32_SCALER_PRAGMA(3) EDUKE32_SCALER_PRAGMA(4)                \
     EDUKE32_SCALER_PRAGMA(5) EDUKE32_SCALER_PRAGMA(6) EDUKE32_SCALER_PRAGMA(7) EDUKE32_SCALER_PRAGMA(8)                \
@@ -105,7 +103,6 @@ extern int32_t tabledivide32_noinline(int32_t n, int32_t d);
 extern int32_t tabledivide64_noinline(int64_t n, int32_t d);
 
 #ifdef GEKKO
-#include <math.h>
 static inline int32_t divscale(int32_t eax, int32_t ebx, int32_t ecx) { return tabledivide64(ldexp(eax, ecx), ebx); }
 #else
 static inline int32_t divscale(int32_t eax, int32_t ebx, int32_t ecx)
diff --git a/source/build/include/winbits.h b/source/build/include/winbits.h
index adb50b07b..9f15f2cb7 100644
--- a/source/build/include/winbits.h
+++ b/source/build/include/winbits.h
@@ -1,6 +1,6 @@
 // Windows layer-independent code
 
-#include <compat.h>
+#include "compat.h"
 
 #define WindowClass "buildapp"
 
diff --git a/source/build/src/SDLMain.mm b/source/build/src/SDLMain.mm
index 93970d135..280b1a869 100644
--- a/source/build/src/SDLMain.mm
+++ b/source/build/src/SDLMain.mm
@@ -21,7 +21,6 @@
 #import <Cocoa/Cocoa.h>
 
 #include <sys/param.h> /* for MAXPATHLEN */
-#include <unistd.h>
 
 /* For some reason, Apple removed setAppleMenu from the headers in 10.4,
  but the method still is there and works. To avoid warnings, we declare
diff --git a/source/build/src/animvpx.cpp b/source/build/src/animvpx.cpp
index 18152a76b..a48ca4019 100644
--- a/source/build/src/animvpx.cpp
+++ b/source/build/src/animvpx.cpp
@@ -10,7 +10,7 @@
 #endif
 
 
-#include <stdint.h>
+#include "compat.h"
 
 #include "compat.h"
 #include "baselayer.h"
diff --git a/source/build/src/cache1d.cpp b/source/build/src/cache1d.cpp
index 98b8b4aa2..418ceb176 100644
--- a/source/build/src/cache1d.cpp
+++ b/source/build/src/cache1d.cpp
@@ -5,29 +5,16 @@
 // This file has been modified from Ken Silverman's original release
 // by Jonathon Fowler (jf@jonof.id.au)
 
+#include "compat.h"
 
 #ifdef CACHE1D_COMPRESS_ONLY
 // Standalone libcache1d.so containing only the compression/decompression
 // functions.
-# include <stdint.h>
-# include <stdio.h>
-# include <string.h>
-# include <stddef.h>
-# include <assert.h>
-
-# define BFILE FILE
 # define C1D_STATIC
-# define B_LITTLE16(x) (x)
-# define B_LITTLE32(x) (x)
-# define Bmemset memset
-# define Bmemcpy memcpy
-# define Bassert assert
-# define bsize_t size_t
 #else
 // cache1d.o for EDuke32
 # define C1D_STATIC static
 
-#include "compat.h"
 #ifdef _WIN32
 // for FILENAME_CASE_CHECK
 # define NEED_SHELLAPI_H
diff --git a/source/build/src/compat.cpp b/source/build/src/compat.cpp
index 098f707ee..f84e3958c 100644
--- a/source/build/src/compat.cpp
+++ b/source/build/src/compat.cpp
@@ -7,7 +7,6 @@
 #ifdef _WIN32
 # define NEED_SHLOBJ_H
 # include "windows_inc.h"
-# include <direct.h>
 #elif __APPLE__
 # include "osxbits.h"
 #endif
diff --git a/source/build/src/dynamicgtk.cpp b/source/build/src/dynamicgtk.cpp
index a1ec14668..fd37e76e9 100644
--- a/source/build/src/dynamicgtk.cpp
+++ b/source/build/src/dynamicgtk.cpp
@@ -1,6 +1,5 @@
+#include "compat.h"
 #include <dlfcn.h>
-#include <stdio.h>
-#include <string.h>
 
 #define dynamicgtkfoo__
 #include "dynamicgtk.h"
diff --git a/source/build/src/engine.cpp b/source/build/src/engine.cpp
index 5e9450070..13aeabeec 100644
--- a/source/build/src/engine.cpp
+++ b/source/build/src/engine.cpp
@@ -31,8 +31,6 @@
 # include "polymost.h"
 #endif
 
-#include <math.h>  // pow
-
 #include "engine_priv.h"
 #include "palette.h"
 
diff --git a/source/build/src/glbuild.cpp b/source/build/src/glbuild.cpp
index 78be2d6ab..935a35758 100644
--- a/source/build/src/glbuild.cpp
+++ b/source/build/src/glbuild.cpp
@@ -1,9 +1,6 @@
 #include "compat.h"
 #include "glbuild.h"
 #include "baselayer.h"
-#include <stdlib.h>
-#include <string.h>
-#include <stdio.h>
 
 #if defined USE_OPENGL
 
diff --git a/source/build/src/gtkbits.cpp b/source/build/src/gtkbits.cpp
index 03b759211..9bb6ea178 100644
--- a/source/build/src/gtkbits.cpp
+++ b/source/build/src/gtkbits.cpp
@@ -1,9 +1,4 @@
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <unistd.h>
-#include <string.h>
-#include <stdio.h>
-#include <stdlib.h>
+#include "compat.h"
 
 #include "dynamicgtk.h"
 
diff --git a/source/build/src/kplib.cpp b/source/build/src/kplib.cpp
index 5c7f66824..5294540a5 100644
--- a/source/build/src/kplib.cpp
+++ b/source/build/src/kplib.cpp
@@ -32,16 +32,9 @@ credits.
 #include "compat.h"
 #include "baselayer.h"
 #include "kplib.h"
-#include <string.h>
-#include <fcntl.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <stdio.h>
-#include <stdlib.h>
 #include "pragmas.h"
 
 #if !defined(_WIN32)
-#include <unistd.h>
 #include <dirent.h>
 # if !defined __INTEL_COMPILER
 typedef long long  __int64;
diff --git a/source/build/src/mdsprite.cpp b/source/build/src/mdsprite.cpp
index 679269b23..df8e82d4d 100644
--- a/source/build/src/mdsprite.cpp
+++ b/source/build/src/mdsprite.cpp
@@ -17,9 +17,6 @@
 #include "common.h"
 #include "palette.h"
 
-#include <math.h>
-#include <float.h>
-
 static int32_t curextra=MAXTILES;
 
 #define MIN_CACHETIME_PRINT 10
diff --git a/source/build/src/polymer.cpp b/source/build/src/polymer.cpp
index 7f945ec01..810458152 100644
--- a/source/build/src/polymer.cpp
+++ b/source/build/src/polymer.cpp
@@ -2,7 +2,7 @@
 
 #if defined USE_OPENGL && defined POLYMER
 
-#include <math.h>
+#include "compat.h"
 
 #define POLYMER_C
 #include "polymer.h"
diff --git a/source/build/src/polymost.cpp b/source/build/src/polymost.cpp
index 335dba8f8..3cc5fee52 100644
--- a/source/build/src/polymost.cpp
+++ b/source/build/src/polymost.cpp
@@ -33,9 +33,6 @@ int32_t rendmode=0;
 int32_t usemodels=1;
 int32_t usehightile=1;
 
-#include <math.h> //<-important!
-#include <float.h>
-
 typedef struct { float x, cy[2], fy[2]; int32_t tag; int16_t n, p, ctag, ftag; } vsptyp;
 #define VSPMAX 4096 //<- careful!
 static vsptyp vsp[VSPMAX];
diff --git a/source/build/src/rawinput.cpp b/source/build/src/rawinput.cpp
index 0be1aeb1c..4070d0cc0 100644
--- a/source/build/src/rawinput.cpp
+++ b/source/build/src/rawinput.cpp
@@ -1,7 +1,7 @@
 
 #include "windows_inc.h"
 
-#include <malloc.h>
+#include "compat.h"
 #include "rawinput.h"
 #include "winlayer.h"
 #include "scancodes.h"
diff --git a/source/build/src/screenshot.cpp b/source/build/src/screenshot.cpp
index 7080afee7..b776f9655 100644
--- a/source/build/src/screenshot.cpp
+++ b/source/build/src/screenshot.cpp
@@ -1,8 +1,5 @@
 
-#if (PNG_LIBPNG_VER > 10599)
-# include <string.h>
-#endif
-
+#include "compat.h"
 #include "build.h"
 #include "editor.h"
 
diff --git a/source/build/src/scriptfile.cpp b/source/build/src/scriptfile.cpp
index e046c1787..a7783d3a2 100644
--- a/source/build/src/scriptfile.cpp
+++ b/source/build/src/scriptfile.cpp
@@ -10,7 +10,6 @@
 #include "baselayer.h"
 #include "compat.h"
 #include "cache1d.h"
-#include <math.h>
 
 
 #define ISWS(x) ((x == ' ') || (x == '\t') || (x == '\r') || (x == '\n'))
diff --git a/source/build/src/sdlayer.cpp b/source/build/src/sdlayer.cpp
index b8ad36e8c..c4e5033ae 100644
--- a/source/build/src/sdlayer.cpp
+++ b/source/build/src/sdlayer.cpp
@@ -8,11 +8,9 @@
 #ifndef __STDC_LIMIT_MACROS
 #define __STDC_LIMIT_MACROS
 #endif
-#include <stdlib.h>
-#include <math.h>  // pow
+#include "compat.h"
 #include <signal.h>
 #include "sdl_inc.h"
-#include "compat.h"
 #include "renderlayer.h"
 #include "cache1d.h"
 //#include "pragmas.h"
diff --git a/source/build/src/voxmodel.cpp b/source/build/src/voxmodel.cpp
index 628f2fa4f..923b7a6d6 100644
--- a/source/build/src/voxmodel.cpp
+++ b/source/build/src/voxmodel.cpp
@@ -16,8 +16,6 @@
 #include "kplib.h"
 #include "palette.h"
 
-#include <math.h>
-
 
 //For loading/conversion only
 static vec3_t voxsiz;
diff --git a/source/build/src/winlayer.cpp b/source/build/src/winlayer.cpp
index adb8424fd..1e89ccc3b 100644
--- a/source/build/src/winlayer.cpp
+++ b/source/build/src/winlayer.cpp
@@ -1,8 +1,7 @@
 // Windows DIB/DirectDraw interface layer for the Build Engine
 // Originally by Jonathon Fowler (jf@jonof.id.au)
 
-#include <math.h>
-#include <malloc.h>
+#include "compat.h"
 
 #include "build.h"
 
diff --git a/source/duke3d/src/gameexec.cpp b/source/duke3d/src/gameexec.cpp
index 299070090..72e6e7d66 100644
--- a/source/duke3d/src/gameexec.cpp
+++ b/source/duke3d/src/gameexec.cpp
@@ -20,10 +20,8 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */
 //-------------------------------------------------------------------------
 
-
+#include "compat.h"
 #include "duke3d.h"
-#include <time.h>
-#include <math.h>  // sqrt
 
 #include "scriplib.h"
 #include "savegame.h"
diff --git a/source/duke3d/src/lunatic/lunatic_game.cpp b/source/duke3d/src/lunatic/lunatic_game.cpp
index fbc4ae604..2c5a08e1f 100644
--- a/source/duke3d/src/lunatic/lunatic_game.cpp
+++ b/source/duke3d/src/lunatic/lunatic_game.cpp
@@ -2,11 +2,6 @@
 
 #include "compat.h"
 
-#include <stdint.h>
-#include <stdlib.h>  // getenv
-#include <errno.h>
-#include <string.h>  // strerror
-
 #ifdef __cplusplus
 extern "C" {
 #endif
diff --git a/source/duke3d/src/m32exec.cpp b/source/duke3d/src/m32exec.cpp
index b279b0608..29ff15fbc 100644
--- a/source/duke3d/src/m32exec.cpp
+++ b/source/duke3d/src/m32exec.cpp
@@ -20,8 +20,7 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */
 //-------------------------------------------------------------------------
 
-#include <time.h>
-#include <stdlib.h>
+#include "compat.h"
 
 #include "m32script.h"
 #include "m32def.h"
diff --git a/source/duke3d/src/mdump.cpp b/source/duke3d/src/mdump.cpp
index 745f8ba66..2e2709547 100644
--- a/source/duke3d/src/mdump.cpp
+++ b/source/duke3d/src/mdump.cpp
@@ -1,12 +1,7 @@
 
+#include "compat.h"
 #include "mdump.h"
 
-#include <assert.h>
-
-#include <cstdlib>
-#include <cstdio>
-#include <cstring>
-
 #include <tchar.h>
 LPCSTR MiniDumper::m_szAppName;
 
diff --git a/source/duke3d/src/menus.cpp b/source/duke3d/src/menus.cpp
index 480721768..60b41758b 100644
--- a/source/duke3d/src/menus.cpp
+++ b/source/duke3d/src/menus.cpp
@@ -20,6 +20,7 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */
 //-------------------------------------------------------------------------
 
+#include "compat.h"
 #include "duke3d.h"
 #include "osdcmds.h"
 #include "savegame.h"
@@ -29,8 +30,6 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 #include "menus.h"
 #include "cheats.h"
 
-#include <sys/stat.h>
-
 #include "in_android.h"
 #ifndef __ANDROID__
 droidinput_t droidinput;
diff --git a/source/duke3d/src/midi.cpp b/source/duke3d/src/midi.cpp
index 723d78c6c..c8d4a2782 100644
--- a/source/duke3d/src/midi.cpp
+++ b/source/duke3d/src/midi.cpp
@@ -31,8 +31,7 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
    (c) Copyright 1994 James R. Dose.  All Rights Reserved.
 **********************************************************************/
 
-#include <stdlib.h>
-#include <string.h>
+#include "compat.h"
 #include "standard.h"
 #include "music.h"
 #include "_midi.h"
diff --git a/source/duke3d/src/music.cpp b/source/duke3d/src/music.cpp
index 33cdd9810..5b879fcbe 100644
--- a/source/duke3d/src/music.cpp
+++ b/source/duke3d/src/music.cpp
@@ -20,12 +20,10 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */
 //-------------------------------------------------------------------------
 
-#include <stdio.h>
-#include <stdlib.h>
+#include "compat.h"
 #include "music.h"
 #include "midi.h"
 #include "mpu401.h"
-#include "compat.h"
 
 #ifndef TRUE
 #define TRUE (1 == 1)
diff --git a/source/duke3d/src/osdfuncs.cpp b/source/duke3d/src/osdfuncs.cpp
index a5f94d8ab..58fd8a41d 100644
--- a/source/duke3d/src/osdfuncs.cpp
+++ b/source/duke3d/src/osdfuncs.cpp
@@ -20,7 +20,6 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */
 //-------------------------------------------------------------------------
 #include "compat.h"
-#include <math.h>
 #include "duke3d.h"
 #include "build.h"
 #include "namesdyn.h"
diff --git a/source/duke3d/src/sdlmusic.cpp b/source/duke3d/src/sdlmusic.cpp
index cad28c5e3..00c5f163a 100644
--- a/source/duke3d/src/sdlmusic.cpp
+++ b/source/duke3d/src/sdlmusic.cpp
@@ -30,9 +30,6 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 
 #include "compat.h"
 
-#include <stdio.h>
-#include <errno.h>
-
 #include "duke3d.h"
 #include "cache1d.h"
 
@@ -44,9 +41,7 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 #endif
 
 #if defined FORK_EXEC_MIDI  // fork/exec based external midi player
-#include <stdlib.h>
 #include <signal.h>
-#include <unistd.h>
 #include <sys/mman.h>
 #include <sys/wait.h>
 static char **external_midi_argv;
diff --git a/source/duke3d/src/sounds_mapster32.cpp b/source/duke3d/src/sounds_mapster32.cpp
index 946fa947a..f2d7f192b 100644
--- a/source/duke3d/src/sounds_mapster32.cpp
+++ b/source/duke3d/src/sounds_mapster32.cpp
@@ -22,9 +22,6 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 
 // Stripped sounds.c for use in Mapster32, breaks all ties to game & music
 
-#include <stdio.h>
-#include <string.h>
-
 #include "compat.h"
 #include "baselayer.h"
 
diff --git a/source/duke3d/src/startgtk.game.cpp b/source/duke3d/src/startgtk.game.cpp
index d4abeb50c..611822ed5 100644
--- a/source/duke3d/src/startgtk.game.cpp
+++ b/source/duke3d/src/startgtk.game.cpp
@@ -20,6 +20,8 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */
 //-------------------------------------------------------------------------
 
+#include "compat.h"
+
 #include "gtkpixdata.h"
 
 #if defined(LINKED_GTK)
diff --git a/source/kenbuild/src/startgtk.game.cpp b/source/kenbuild/src/startgtk.game.cpp
index 4c19f71ed..80e457953 100644
--- a/source/kenbuild/src/startgtk.game.cpp
+++ b/source/kenbuild/src/startgtk.game.cpp
@@ -3,12 +3,7 @@
  * template.
  */
 
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <unistd.h>
-#include <string.h>
-#include <stdio.h>
-#include <stdlib.h>
+#include "compat.h"
 
 #include "gtkpixdata.h"
 #include <gdk-pixbuf/gdk-pixdata.h>
diff --git a/source/mact/src/file_lib.cpp b/source/mact/src/file_lib.cpp
index 899893041..7c389fc04 100644
--- a/source/mact/src/file_lib.cpp
+++ b/source/mact/src/file_lib.cpp
@@ -31,12 +31,6 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */
 //-------------------------------------------------------------------------
 
-#include <stdlib.h>
-#ifndef _MSC_VER
-#include <unistd.h>
-#endif
-#include <fcntl.h>
-#include <errno.h>
 #include "compat.h"
 
 #include "file_lib.h"
diff --git a/source/mact/src/scriplib.cpp b/source/mact/src/scriplib.cpp
index 82a95824d..efaf8ad04 100644
--- a/source/mact/src/scriplib.cpp
+++ b/source/mact/src/scriplib.cpp
@@ -38,9 +38,6 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 #include "scriplib.h"
 #include "file_lib.h"
 #include "_scrplib.h"
-#include <string.h>
-#include <stdio.h>
-#include <ctype.h>
 
 static script_t *scriptfiles[MAXSCRIPTFILES];
 
diff --git a/source/sw/src/saveable.cpp b/source/sw/src/saveable.cpp
index 4a7fdce7a..296683fee 100644
--- a/source/sw/src/saveable.cpp
+++ b/source/sw/src/saveable.cpp
@@ -23,7 +23,6 @@
 
 #include "compat.h"
 #include "saveable.h"
-#include <stdlib.h>
 
 #define maxModules 35
 
diff --git a/source/sw/src/sounds.cpp b/source/sw/src/sounds.cpp
index 631d659a6..ab43120b7 100644
--- a/source/sw/src/sounds.cpp
+++ b/source/sw/src/sounds.cpp
@@ -23,7 +23,7 @@ Original Source: 1997 - Frank Maddin and Jim Norwood
 Prepared for public release: 03/28/2005 - Charlie Wiederhold, 3D Realms
 */
 //-------------------------------------------------------------------------
-#include <math.h>
+#include "compat.h"
 #include "build.h"
 #include "cache1d.h"
 
diff --git a/source/sw/src/startgtk.game.cpp b/source/sw/src/startgtk.game.cpp
index 5ff43df37..43bb6d932 100644
--- a/source/sw/src/startgtk.game.cpp
+++ b/source/sw/src/startgtk.game.cpp
@@ -3,12 +3,7 @@
  * template.
  */
 
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <unistd.h>
-#include <string.h>
-#include <stdio.h>
-#include <stdlib.h>
+#include "compat.h"
 
 #include <gdk-pixbuf/gdk-pixdata.h>
 #include <gdk-pixbuf/gdk-pixbuf.h>
diff --git a/source/tools/src/arttool.cpp b/source/tools/src/arttool.cpp
index 49577a999..feed7630e 100644
--- a/source/tools/src/arttool.cpp
+++ b/source/tools/src/arttool.cpp
@@ -5,9 +5,6 @@
  */
 // Bstring and C++ STL --> C conversion by Hendricks266
 
-#include <stdio.h>
-#include <string.h>
-
 #include "compat.h"
 
 ////////// Bstring //////////
diff --git a/source/tools/src/bsuite.cpp b/source/tools/src/bsuite.cpp
index 45ca85704..7e07cca14 100644
--- a/source/tools/src/bsuite.cpp
+++ b/source/tools/src/bsuite.cpp
@@ -19,10 +19,6 @@
 */
 // DOS 16-bit real mode UI --> portable command line conversion by Hendricks266
 
-#include <stdlib.h>
-#include <stdio.h>
-#include <string.h>
-#include <ctype.h>
 #include "compat.h"
 
 const char APP_NAME[] = "Build Game Customization Suite v0.2-EDuke32";
diff --git a/source/tools/src/cacheinfo.cpp b/source/tools/src/cacheinfo.cpp
index e719eeb6b..7690b6903 100644
--- a/source/tools/src/cacheinfo.cpp
+++ b/source/tools/src/cacheinfo.cpp
@@ -1,10 +1,7 @@
 // XXX: This program is not in sync with EDuke32 (e.g. texcacheheader type).
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <dirent.h>
-#include <sys/stat.h>
 #include "compat.h"
+#include <dirent.h>
 
 #define GL_COMPRESSED_RGB_S3TC_DXT1_EXT   0x83F0
 #define GL_COMPRESSED_RGBA_S3TC_DXT1_EXT  0x83F1
diff --git a/source/tools/src/generateicon.cpp b/source/tools/src/generateicon.cpp
index e3702ae7b..16f7096e3 100644
--- a/source/tools/src/generateicon.cpp
+++ b/source/tools/src/generateicon.cpp
@@ -1,8 +1,6 @@
 
-#include <stdio.h>
-#include "inttypes.h"
-#include "kplib.h"
 #include "compat.h"
+#include "kplib.h"
 
 struct icon {
     int32_t width,height;
diff --git a/source/tools/src/givedepth.cpp b/source/tools/src/givedepth.cpp
index 67ec68dcb..eac2c3443 100644
--- a/source/tools/src/givedepth.cpp
+++ b/source/tools/src/givedepth.cpp
@@ -1,6 +1,4 @@
-#include <stdio.h>
-#include <stdlib.h>
-#include <fcntl.h>
+#include "compat.h"
 
 #define MAXNUMTILES 256
 
diff --git a/source/tools/src/ivfrate.cpp b/source/tools/src/ivfrate.cpp
index 557bb2354..b82f56aef 100644
--- a/source/tools/src/ivfrate.cpp
+++ b/source/tools/src/ivfrate.cpp
@@ -1,14 +1,5 @@
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <errno.h>
-
-#include <fcntl.h>
-#include <unistd.h>
-
-#include <stdint.h>
-#define Bmemcmp memcmp
+#include "compat.h"
 #ifndef USE_OPENGL
 # define USE_OPENGL
 #endif
diff --git a/source/tools/src/kmd2tool.cpp b/source/tools/src/kmd2tool.cpp
index 576e3713c..7a237e8e1 100644
--- a/source/tools/src/kmd2tool.cpp
+++ b/source/tools/src/kmd2tool.cpp
@@ -1,6 +1,4 @@
 
-#include <stdio.h>
-#include <math.h>
 #include "compat.h"
 
 typedef struct { float x, y, z; } point3d;
diff --git a/source/tools/src/makesdlkeytrans.cpp b/source/tools/src/makesdlkeytrans.cpp
index d09b82a4a..02d3b58d0 100644
--- a/source/tools/src/makesdlkeytrans.cpp
+++ b/source/tools/src/makesdlkeytrans.cpp
@@ -1,7 +1,6 @@
 // gcc b.c -Lc:/mingw32/lib -lmingw32 -lSDLmain -lSDL
 
-#include <stdio.h>
-#include <string.h>
+#include "compat.h"
 #include "sdl_inc.h"
 
 #include "sdlkeytrans.cpp"
diff --git a/source/tools/src/map2stl.cpp b/source/tools/src/map2stl.cpp
index e61c7d3d5..7f85f13ab 100644
--- a/source/tools/src/map2stl.cpp
+++ b/source/tools/src/map2stl.cpp
@@ -1,5 +1,3 @@
-
-#include <math.h>
 #include "compat.h"
 
 #define PI 3.141592653589793
diff --git a/source/tools/src/md2tool.cpp b/source/tools/src/md2tool.cpp
index c4f39204d..ad962d9c7 100644
--- a/source/tools/src/md2tool.cpp
+++ b/source/tools/src/md2tool.cpp
@@ -4,9 +4,6 @@
 #include "glbuild.h"
 #include "mdsprite.h"
 
-#include <stdio.h>
-#include <errno.h>
-
 
 static md2head_t head;
 
diff --git a/source/tools/src/mkpalette.cpp b/source/tools/src/mkpalette.cpp
index ba027cb85..2f7ddc4a0 100644
--- a/source/tools/src/mkpalette.cpp
+++ b/source/tools/src/mkpalette.cpp
@@ -1,6 +1,4 @@
-#include <stdio.h>
-#include <string.h>
-#include <math.h>
+#include "compat.h"
 
 struct hsv {
     float h, s, v;
diff --git a/source/tools/src/unpackssi.cpp b/source/tools/src/unpackssi.cpp
index f24f01059..9dfe5ae49 100644
--- a/source/tools/src/unpackssi.cpp
+++ b/source/tools/src/unpackssi.cpp
@@ -39,9 +39,7 @@
     NOTE: This program does not fall under BUILDLIC.
 */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <stdint.h>
+#include "compat.h"
 
 int main(int argc, char **argv)
 {