diff --git a/src/dehacked.c b/src/dehacked.c
index b7e874b1..2fed963f 100644
--- a/src/dehacked.c
+++ b/src/dehacked.c
@@ -7769,7 +7769,7 @@ fixed_t get_number(const char *word)
 #endif
 }
 
-void FUNCMATH DEH_Check(void)
+void DEH_Check(void)
 {
 #if defined(_DEBUG) || defined(PARANOIA)
 	const size_t dehstates = sizeof(STATE_LIST)/sizeof(const char*);
diff --git a/src/f_finale.c b/src/f_finale.c
index fb1387c1..a50e4a5b 100644
--- a/src/f_finale.c
+++ b/src/f_finale.c
@@ -1401,6 +1401,7 @@ void F_StartGameEnd(void)
 //
 void F_GameEndDrawer(void)
 {
+	// this function does nothing
 }
 
 //
diff --git a/src/f_finale.h b/src/f_finale.h
index 1f23643b..8ee02bdf 100644
--- a/src/f_finale.h
+++ b/src/f_finale.h
@@ -35,7 +35,7 @@ void F_CutsceneTicker(void);
 void F_TitleDemoTicker(void);
 
 // Called by main loop.
-FUNCMATH void F_GameEndDrawer(void);
+void F_GameEndDrawer(void);
 void F_IntroDrawer(void);
 void F_TitleScreenDrawer(void);
 
diff --git a/src/r_plane.h b/src/r_plane.h
index 16c8c12a..dff58669 100644
--- a/src/r_plane.h
+++ b/src/r_plane.h
@@ -87,7 +87,7 @@ extern lighttable_t **planezlight;
 extern fixed_t *yslope;
 extern fixed_t distscale[MAXVIDWIDTH];
 
-FUNCMATH void R_InitPlanes(void);
+void R_InitPlanes(void);
 void R_PortalStoreClipValues(INT32 start, INT32 end, INT16 *ceil, INT16 *floor, fixed_t *scale);
 void R_PortalRestoreClipValues(INT32 start, INT32 end, INT16 *ceil, INT16 *floor, fixed_t *scale);
 void R_ClearPlanes(void);
diff --git a/src/r_splats.h b/src/r_splats.h
index c0ba6881..349d8fa7 100644
--- a/src/r_splats.h
+++ b/src/r_splats.h
@@ -63,11 +63,7 @@ typedef struct floorsplat_s
 fixed_t P_SegLength(seg_t *seg);
 
 // call at P_SetupLevel()
-#if !(defined (WALLSPLATS) || defined (FLOORSPLATS))
-FUNCMATH void R_ClearLevelSplats(void);
-#else
 void R_ClearLevelSplats(void);
-#endif
 
 #ifdef WALLSPLATS
 void R_AddWallSplat(line_t *wallline, INT16 sectorside, const char *patchname, fixed_t top,
diff --git a/src/screen.c b/src/screen.c
index 58c38993..fdd8eb7b 100644
--- a/src/screen.c
+++ b/src/screen.c
@@ -71,11 +71,7 @@ consvar_t cv_scr_depth = {"scr_depth", "16 bits", CV_SAVE, scr_depth_cons_t, NUL
 #endif
 consvar_t cv_renderview = {"renderview", "On", 0, CV_OnOff, NULL, 0, NULL, NULL, 0, 0, NULL};
 
-#ifdef DIRECTFULLSCREEN
-static FUNCMATH void SCR_ChangeFullscreen (void);
-#else
 static void SCR_ChangeFullscreen (void);
-#endif
 
 consvar_t cv_fullscreen = {"fullscreen", "Yes", CV_SAVE|CV_CALL, CV_YesNo, SCR_ChangeFullscreen, 0, NULL, NULL, 0, 0, NULL};
 
diff --git a/src/sdl/i_cdmus.c b/src/sdl/i_cdmus.c
index 3105f512..5d086e73 100644
--- a/src/sdl/i_cdmus.c
+++ b/src/sdl/i_cdmus.c
@@ -12,19 +12,19 @@ consvar_t cd_volume = {"cd_volume","31",CV_SAVE,soundvolume_cons_t, NULL, 0, NUL
 consvar_t cdUpdate  = {"cd_update","1",CV_SAVE, NULL, NULL, 0, NULL, NULL, 0, 0, NULL};
 
 
-FUNCMATH void I_InitCD(void){}
+void I_InitCD(void){}
 
-FUNCMATH void I_StopCD(void){}
+void I_StopCD(void){}
 
-FUNCMATH void I_PauseCD(void){}
+void I_PauseCD(void){}
 
-FUNCMATH void I_ResumeCD(void){}
+void I_ResumeCD(void){}
 
-FUNCMATH void I_ShutdownCD(void){}
+void I_ShutdownCD(void){}
 
-FUNCMATH void I_UpdateCD(void){}
+void I_UpdateCD(void){}
 
-FUNCMATH void I_PlayCD(UINT8 track, UINT8 looping)
+void I_PlayCD(UINT8 track, UINT8 looping)
 {
 	(void)track;
 	(void)looping;
diff --git a/src/sdl/i_system.c b/src/sdl/i_system.c
index 7b14f1f1..9a2baf31 100644
--- a/src/sdl/i_system.c
+++ b/src/sdl/i_system.c
@@ -1927,14 +1927,14 @@ void I_StartupMouse2(void)
 //
 // I_Tactile
 //
-FUNCMATH void I_Tactile(FFType pFFType, const JoyFF_t *FFEffect)
+void I_Tactile(FFType pFFType, const JoyFF_t *FFEffect)
 {
 	// UNUSED.
 	(void)pFFType;
 	(void)FFEffect;
 }
 
-FUNCMATH void I_Tactile2(FFType pFFType, const JoyFF_t *FFEffect)
+void I_Tactile2(FFType pFFType, const JoyFF_t *FFEffect)
 {
 	// UNUSED.
 	(void)pFFType;
@@ -1945,7 +1945,7 @@ FUNCMATH void I_Tactile2(FFType pFFType, const JoyFF_t *FFEffect)
 */
 static ticcmd_t emptycmd;
 
-FUNCMATH ticcmd_t *I_BaseTiccmd(void)
+ticcmd_t *I_BaseTiccmd(void)
 {
 	return &emptycmd;
 }
@@ -1954,7 +1954,7 @@ FUNCMATH ticcmd_t *I_BaseTiccmd(void)
 */
 static ticcmd_t emptycmd2;
 
-FUNCMATH ticcmd_t *I_BaseTiccmd2(void)
+ticcmd_t *I_BaseTiccmd2(void)
 {
 	return &emptycmd2;
 }
@@ -2048,7 +2048,7 @@ tic_t I_GetTime (void)
 //
 //I_StartupTimer
 //
-FUNCMATH void I_StartupTimer(void)
+void I_StartupTimer(void)
 {
 #ifdef _WIN32
 	// for win2k time bug
@@ -2147,11 +2147,11 @@ void I_WaitVBL(INT32 count)
 	SDL_Delay(count);
 }
 
-FUNCMATH void I_BeginRead(void)
+void I_BeginRead(void)
 {
 }
 
-FUNCMATH void I_EndRead(void)
+void I_EndRead(void)
 {
 }
 
@@ -2939,5 +2939,5 @@ const CPUInfoFlags *I_CPUInfo(void)
 }
 
 // note CPUAFFINITY code used to reside here
-FUNCMATH void I_RegisterSysCommands(void) {}
+void I_RegisterSysCommands(void) {}
 #endif
diff --git a/src/sdl/i_video.c b/src/sdl/i_video.c
index 30ef1b27..db88f452 100644
--- a/src/sdl/i_video.c
+++ b/src/sdl/i_video.c
@@ -1053,7 +1053,7 @@ void I_SetPalette(RGBA_t *palette)
 }
 
 // return number of fullscreen + X11 modes
-FUNCMATH INT32 VID_NumModes(void)
+INT32 VID_NumModes(void)
 {
 	if (USE_FULLSCREEN && numVidModes != -1)
 		return numVidModes - firstEntry;
@@ -1061,7 +1061,7 @@ FUNCMATH INT32 VID_NumModes(void)
 		return MAXWINMODES;
 }
 
-FUNCMATH const char *VID_GetModeName(INT32 modeNum)
+const char *VID_GetModeName(INT32 modeNum)
 {
 #if 0
 	if (USE_FULLSCREEN && numVidModes != -1) // fullscreen modes
@@ -1091,7 +1091,7 @@ FUNCMATH const char *VID_GetModeName(INT32 modeNum)
 	return &vidModeName[modeNum][0];
 }
 
-FUNCMATH INT32 VID_GetModeForSize(INT32 w, INT32 h)
+INT32 VID_GetModeForSize(INT32 w, INT32 h)
 {
 	int i;
 	for (i = 0; i < MAXWINMODES; i++)
diff --git a/src/sdl/mixer_sound.c b/src/sdl/mixer_sound.c
index 4d86d7a3..f36f0869 100644
--- a/src/sdl/mixer_sound.c
+++ b/src/sdl/mixer_sound.c
@@ -135,7 +135,7 @@ void I_ShutdownSound(void)
 #endif
 }
 
-FUNCMATH void I_UpdateSound(void)
+void I_UpdateSound(void)
 {
 }
 
@@ -504,7 +504,7 @@ static void mix_gme(void *udata, Uint8 *stream, int len)
 /// Music System
 /// ------------------------
 
-FUNCMATH void I_InitMusic(void)
+void I_InitMusic(void)
 {
 }
 
diff --git a/src/sdl/sdl_sound.c b/src/sdl/sdl_sound.c
index 9f8a3e29..f4796cd8 100644
--- a/src/sdl/sdl_sound.c
+++ b/src/sdl/sdl_sound.c
@@ -219,7 +219,7 @@ static void Snd_UnlockAudio(void) //Alam: Unlock audio data and reinstall audio
 #endif
 }
 
-FUNCMATH static inline Uint16 Snd_LowerRate(Uint16 sr)
+static inline Uint16 Snd_LowerRate(Uint16 sr)
 {
 	if (sr <= audio.freq) // already lowered rate?
 		return sr; // good then
diff --git a/src/sdl12/sdl_sound.c b/src/sdl12/sdl_sound.c
index 01a27153..ed1afd8e 100644
--- a/src/sdl12/sdl_sound.c
+++ b/src/sdl12/sdl_sound.c
@@ -236,7 +236,7 @@ static void Snd_UnlockAudio(void) //Alam: Unlock audio data and reinstall audio
 #endif
 }
 
-FUNCMATH static inline Uint16 Snd_LowerRate(Uint16 sr)
+static inline Uint16 Snd_LowerRate(Uint16 sr)
 {
 	if (sr <= audio.freq) // already lowered rate?
 		return sr; // good then