diff --git a/include/SDL_test_assert.h b/include/SDL_test_assert.h
index 29277e122..60288d3d2 100644
--- a/include/SDL_test_assert.h
+++ b/include/SDL_test_assert.h
@@ -80,12 +80,12 @@ void SDLTest_AssertPass(SDL_PRINTF_FORMAT_STRING const char *assertDescription,
 /**
  * \brief Resets the assert summary counters to zero.
  */
-void SDLTest_ResetAssertSummary();
+void SDLTest_ResetAssertSummary(void);
 
 /**
  * \brief Logs summary of all assertions (total, pass, fail) since last reset as INFO or ERROR.
  */
-void SDLTest_LogAssertSummary();
+void SDLTest_LogAssertSummary(void);
 
 
 /**
@@ -93,7 +93,7 @@ void SDLTest_LogAssertSummary();
  *
  * \returns TEST_RESULT_PASSED, TEST_RESULT_FAILED, or TEST_RESULT_NO_ASSERT
  */
-int SDLTest_AssertSummaryToTestResult();
+int SDLTest_AssertSummaryToTestResult(void);
 
 #ifdef __cplusplus
 }
diff --git a/include/SDL_test_fuzzer.h b/include/SDL_test_fuzzer.h
index 9603652b2..7bab25c06 100644
--- a/include/SDL_test_fuzzer.h
+++ b/include/SDL_test_fuzzer.h
@@ -68,14 +68,14 @@ void SDLTest_FuzzerInit(Uint64 execKey);
  *
  * \returns Generated integer
  */
-Uint8 SDLTest_RandomUint8();
+Uint8 SDLTest_RandomUint8(void);
 
 /**
  * Returns a random Sint8
  *
  * \returns Generated signed integer
  */
-Sint8 SDLTest_RandomSint8();
+Sint8 SDLTest_RandomSint8(void);
 
 
 /**
@@ -83,14 +83,14 @@ Sint8 SDLTest_RandomSint8();
  *
  * \returns Generated integer
  */
-Uint16 SDLTest_RandomUint16();
+Uint16 SDLTest_RandomUint16(void);
 
 /**
  * Returns a random Sint16
  *
  * \returns Generated signed integer
  */
-Sint16 SDLTest_RandomSint16();
+Sint16 SDLTest_RandomSint16(void);
 
 
 /**
@@ -98,7 +98,7 @@ Sint16 SDLTest_RandomSint16();
  *
  * \returns Generated integer
  */
-Sint32 SDLTest_RandomSint32();
+Sint32 SDLTest_RandomSint32(void);
 
 
 /**
@@ -106,14 +106,14 @@ Sint32 SDLTest_RandomSint32();
  *
  * \returns Generated integer
  */
-Uint32 SDLTest_RandomUint32();
+Uint32 SDLTest_RandomUint32(void);
 
 /**
  * Returns random Uint64.
  *
  * \returns Generated integer
  */
-Uint64 SDLTest_RandomUint64();
+Uint64 SDLTest_RandomUint64(void);
 
 
 /**
@@ -121,29 +121,29 @@ Uint64 SDLTest_RandomUint64();
  *
  * \returns Generated signed integer
  */
-Sint64 SDLTest_RandomSint64();
+Sint64 SDLTest_RandomSint64(void);
 
 /**
  * \returns random float in range [0.0 - 1.0[
  */
-float SDLTest_RandomUnitFloat();
+float SDLTest_RandomUnitFloat(void);
 
 /**
  * \returns random double in range [0.0 - 1.0[
  */
-double SDLTest_RandomUnitDouble();
+double SDLTest_RandomUnitDouble(void);
 
 /**
  * \returns random float.
  *
  */
-float SDLTest_RandomFloat();
+float SDLTest_RandomFloat(void);
 
 /**
  * \returns random double.
  *
  */
-double SDLTest_RandomDouble();
+double SDLTest_RandomDouble(void);
 
 /**
  * Returns a random boundary value for Uint8 within the given boundaries.
@@ -338,7 +338,7 @@ Sint32 SDLTest_RandomIntegerInRange(Sint32 min, Sint32 max);
  *
  * \returns Newly allocated random string; or NULL if length was invalid or string could not be allocated.
  */
-char * SDLTest_RandomAsciiString();
+char * SDLTest_RandomAsciiString(void);
 
 
 /**
@@ -371,7 +371,7 @@ char * SDLTest_RandomAsciiStringOfSize(int size);
 /**
  * Returns the invocation count for the fuzzer since last ...FuzzerInit.
  */
-int SDLTest_GetFuzzerInvocationCount();
+int SDLTest_GetFuzzerInvocationCount(void);
 
 /* Ends C function definitions when using C++ */
 #ifdef __cplusplus
diff --git a/include/SDL_test_images.h b/include/SDL_test_images.h
index 8c64b4feb..1debaabb3 100644
--- a/include/SDL_test_images.h
+++ b/include/SDL_test_images.h
@@ -55,17 +55,17 @@ typedef struct SDLTest_SurfaceImage_s {
 } SDLTest_SurfaceImage_t;
 
 /* Test images */
-SDL_Surface *SDLTest_ImageBlit();
-SDL_Surface *SDLTest_ImageBlitColor();
-SDL_Surface *SDLTest_ImageBlitAlpha();
-SDL_Surface *SDLTest_ImageBlitBlendAdd();
-SDL_Surface *SDLTest_ImageBlitBlend();
-SDL_Surface *SDLTest_ImageBlitBlendMod();
-SDL_Surface *SDLTest_ImageBlitBlendNone();
-SDL_Surface *SDLTest_ImageBlitBlendAll();
-SDL_Surface *SDLTest_ImageFace();
-SDL_Surface *SDLTest_ImagePrimitives();
-SDL_Surface *SDLTest_ImagePrimitivesBlend();
+SDL_Surface *SDLTest_ImageBlit(void);
+SDL_Surface *SDLTest_ImageBlitColor(void);
+SDL_Surface *SDLTest_ImageBlitAlpha(void);
+SDL_Surface *SDLTest_ImageBlitBlendAdd(void);
+SDL_Surface *SDLTest_ImageBlitBlend(void);
+SDL_Surface *SDLTest_ImageBlitBlendMod(void);
+SDL_Surface *SDLTest_ImageBlitBlendNone(void);
+SDL_Surface *SDLTest_ImageBlitBlendAll(void);
+SDL_Surface *SDLTest_ImageFace(void);
+SDL_Surface *SDLTest_ImagePrimitives(void);
+SDL_Surface *SDLTest_ImagePrimitivesBlend(void);
 
 /* Ends C function definitions when using C++ */
 #ifdef __cplusplus
diff --git a/src/SDL.c b/src/SDL.c
index 9eef00cd3..ff2e938e0 100644
--- a/src/SDL.c
+++ b/src/SDL.c
@@ -36,10 +36,7 @@
 
 /* Initialization/Cleanup routines */
 #if !SDL_TIMERS_DISABLED
-extern int SDL_TimerInit(void);
-extern void SDL_TimerQuit(void);
-extern void SDL_TicksInit(void);
-extern void SDL_TicksQuit(void);
+# include "timer/SDL_timer_c.h"
 #endif
 #if SDL_VIDEO_DRIVER_WINDOWS
 extern int SDL_HelperWindowCreate(void);
diff --git a/src/audio/SDL_audio.c b/src/audio/SDL_audio.c
index 460852d7f..c7af699b5 100644
--- a/src/audio/SDL_audio.c
+++ b/src/audio/SDL_audio.c
@@ -33,36 +33,6 @@
 static SDL_AudioDriver current_audio;
 static SDL_AudioDevice *open_devices[16];
 
-/*
- * Not all of these will be compiled and linked in, but it's convenient
- *  to have a complete list here and saves yet-another block of #ifdefs...
- *  Please see bootstrap[], below, for the actual #ifdef mess.
- */
-extern AudioBootStrap PULSEAUDIO_bootstrap;
-extern AudioBootStrap ALSA_bootstrap;
-extern AudioBootStrap SNDIO_bootstrap;
-extern AudioBootStrap BSD_AUDIO_bootstrap;
-extern AudioBootStrap DSP_bootstrap;
-extern AudioBootStrap QSAAUDIO_bootstrap;
-extern AudioBootStrap SUNAUDIO_bootstrap;
-extern AudioBootStrap ARTS_bootstrap;
-extern AudioBootStrap ESD_bootstrap;
-extern AudioBootStrap NACLAUDIO_bootstrap;
-extern AudioBootStrap NAS_bootstrap;
-extern AudioBootStrap XAUDIO2_bootstrap;
-extern AudioBootStrap DSOUND_bootstrap;
-extern AudioBootStrap WINMM_bootstrap;
-extern AudioBootStrap PAUDIO_bootstrap;
-extern AudioBootStrap HAIKUAUDIO_bootstrap;
-extern AudioBootStrap COREAUDIO_bootstrap;
-extern AudioBootStrap DISKAUDIO_bootstrap;
-extern AudioBootStrap DUMMYAUDIO_bootstrap;
-extern AudioBootStrap FUSIONSOUND_bootstrap;
-extern AudioBootStrap ANDROIDAUDIO_bootstrap;
-extern AudioBootStrap PSPAUDIO_bootstrap;
-extern AudioBootStrap SNDIO_bootstrap;
-extern AudioBootStrap EMSCRIPTENAUDIO_bootstrap;
-
 /* Available audio drivers */
 static const AudioBootStrap *const bootstrap[] = {
 #if SDL_AUDIO_DRIVER_PULSEAUDIO
diff --git a/src/audio/SDL_sysaudio.h b/src/audio/SDL_sysaudio.h
index 943169bf7..320ade023 100644
--- a/src/audio/SDL_sysaudio.h
+++ b/src/audio/SDL_sysaudio.h
@@ -200,6 +200,78 @@ typedef struct AudioBootStrap
     int demand_only;  /* 1==request explicitly, or it won't be available. */
 } AudioBootStrap;
 
+#if SDL_AUDIO_DRIVER_PULSEAUDIO
+extern AudioBootStrap PULSEAUDIO_bootstrap;
+#endif
+#if SDL_AUDIO_DRIVER_ALSA
+extern AudioBootStrap ALSA_bootstrap;
+#endif
+#if SDL_AUDIO_DRIVER_SNDIO
+extern AudioBootStrap SNDIO_bootstrap;
+#endif
+#if SDL_AUDIO_DRIVER_BSD
+extern AudioBootStrap BSD_AUDIO_bootstrap;
+#endif
+#if SDL_AUDIO_DRIVER_OSS
+extern AudioBootStrap DSP_bootstrap;
+#endif
+#if SDL_AUDIO_DRIVER_QSA
+extern AudioBootStrap QSAAUDIO_bootstrap;
+#endif
+#if SDL_AUDIO_DRIVER_SUNAUDIO
+extern AudioBootStrap SUNAUDIO_bootstrap;
+#endif
+#if SDL_AUDIO_DRIVER_ARTS
+extern AudioBootStrap ARTS_bootstrap;
+#endif
+#if SDL_AUDIO_DRIVER_ESD
+extern AudioBootStrap ESD_bootstrap;
+#endif
+#if SDL_AUDIO_DRIVER_NACL
+extern AudioBootStrap NACLAUDIO_bootstrap;
+#endif
+#if SDL_AUDIO_DRIVER_NAS
+extern AudioBootStrap NAS_bootstrap;
+#endif
+#if SDL_AUDIO_DRIVER_XAUDIO2
+extern AudioBootStrap XAUDIO2_bootstrap;
+#endif
+#if SDL_AUDIO_DRIVER_DSOUND
+extern AudioBootStrap DSOUND_bootstrap;
+#endif
+#if SDL_AUDIO_DRIVER_WINMM
+extern AudioBootStrap WINMM_bootstrap;
+#endif
+#if SDL_AUDIO_DRIVER_PAUDIO
+extern AudioBootStrap PAUDIO_bootstrap;
+#endif
+#if SDL_AUDIO_DRIVER_HAIKU
+extern AudioBootStrap HAIKUAUDIO_bootstrap;
+#endif
+#if SDL_AUDIO_DRIVER_COREAUDIO
+extern AudioBootStrap COREAUDIO_bootstrap;
+#endif
+#if SDL_AUDIO_DRIVER_DISK
+extern AudioBootStrap DISKAUDIO_bootstrap;
+#endif
+#if SDL_AUDIO_DRIVER_DUMMY
+extern AudioBootStrap DUMMYAUDIO_bootstrap;
+#endif
+#if SDL_AUDIO_DRIVER_FUSIONSOUND
+extern AudioBootStrap FUSIONSOUND_bootstrap;
+#endif
+#if SDL_AUDIO_DRIVER_ANDROID
+extern AudioBootStrap ANDROIDAUDIO_bootstrap;
+#endif
+#if SDL_AUDIO_DRIVER_PSP
+extern AudioBootStrap PSPAUDIO_bootstrap;
+#endif
+#if SDL_AUDIO_DRIVER_EMSCRIPTEN
+extern AudioBootStrap EMSCRIPTENAUDIO_bootstrap;
+#endif
+
+
+
 #endif /* _SDL_sysaudio_h */
 
 /* vi: set ts=4 sw=4 expandtab: */
diff --git a/src/core/linux/SDL_ime.h b/src/core/linux/SDL_ime.h
index 22b31de39..35c42e279 100644
--- a/src/core/linux/SDL_ime.h
+++ b/src/core/linux/SDL_ime.h
@@ -27,12 +27,12 @@
 #include "SDL_stdinc.h"
 #include "SDL_rect.h"
 
-extern SDL_bool SDL_IME_Init();
-extern void SDL_IME_Quit();
+extern SDL_bool SDL_IME_Init(void);
+extern void SDL_IME_Quit(void);
 extern void SDL_IME_SetFocus(SDL_bool focused);
-extern void SDL_IME_Reset();
+extern void SDL_IME_Reset(void);
 extern SDL_bool SDL_IME_ProcessKeyEvent(Uint32 keysym, Uint32 keycode);
 extern void SDL_IME_UpdateTextRect(SDL_Rect *rect);
-extern void SDL_IME_PumpEvents();
+extern void SDL_IME_PumpEvents(void);
 
 #endif /* _SDL_ime_h */
diff --git a/src/core/linux/SDL_udev.c b/src/core/linux/SDL_udev.c
index ae78ddd68..a80b34434 100644
--- a/src/core/linux/SDL_udev.c
+++ b/src/core/linux/SDL_udev.c
@@ -280,7 +280,7 @@ SDL_UDEV_LoadLibrary(void)
 #define BITS_PER_LONG           (sizeof(unsigned long) * 8)
 #define NBITS(x)                ((((x)-1)/BITS_PER_LONG)+1)
 #define OFF(x)                  ((x)%BITS_PER_LONG)
-#define BIT(x)                  (1UL<<OFF(x))
+/* #define BIT(x)                  (1UL<<OFF(x)) */
 #define LONG(x)                 ((x)/BITS_PER_LONG)
 #define test_bit(bit, array)    ((array[LONG(bit)] >> OFF(bit)) & 1)
 
diff --git a/src/events/SDL_gesture.c b/src/events/SDL_gesture.c
index 43914202c..158c8d535 100644
--- a/src/events/SDL_gesture.c
+++ b/src/events/SDL_gesture.c
@@ -71,9 +71,9 @@ typedef struct {
     SDL_bool recording;
 } SDL_GestureTouch;
 
-SDL_GestureTouch *SDL_gestureTouch;
-int SDL_numGestureTouches = 0;
-SDL_bool recordAll;
+static SDL_GestureTouch *SDL_gestureTouch;
+static int SDL_numGestureTouches = 0;
+static SDL_bool recordAll;
 
 #if 0
 static void PrintPath(SDL_FloatPoint *path)
@@ -468,7 +468,7 @@ static SDL_GestureTouch * SDL_GetGestureTouch(SDL_TouchID id)
     return NULL;
 }
 
-int SDL_SendGestureMulti(SDL_GestureTouch* touch,float dTheta,float dDist)
+static int SDL_SendGestureMulti(SDL_GestureTouch* touch,float dTheta,float dDist)
 {
     SDL_Event event;
     event.mgesture.type = SDL_MULTIGESTURE;
diff --git a/src/events/SDL_mouse.c b/src/events/SDL_mouse.c
index 4236a9901..fb4fae747 100644
--- a/src/events/SDL_mouse.c
+++ b/src/events/SDL_mouse.c
@@ -82,6 +82,7 @@ SDL_GetMouseFocus(void)
     return mouse->focus;
 }
 
+#if 0
 void
 SDL_ResetMouse(void)
 {
@@ -98,6 +99,7 @@ SDL_ResetMouse(void)
     }
     SDL_assert(mouse->buttonstate == 0);
 }
+#endif
 
 void
 SDL_SetMouseFocus(SDL_Window * window)
diff --git a/src/events/SDL_touch.c b/src/events/SDL_touch.c
index c73827c96..918cf38c6 100644
--- a/src/events/SDL_touch.c
+++ b/src/events/SDL_touch.c
@@ -92,7 +92,7 @@ SDL_GetFingerIndex(const SDL_Touch * touch, SDL_FingerID fingerid)
     return -1;
 }
 
-SDL_Finger *
+static SDL_Finger *
 SDL_GetFinger(const SDL_Touch * touch, SDL_FingerID id)
 {
     int index = SDL_GetFingerIndex(touch, id);
diff --git a/src/haptic/SDL_haptic.c b/src/haptic/SDL_haptic.c
index ddce908d6..f01a5939c 100644
--- a/src/haptic/SDL_haptic.c
+++ b/src/haptic/SDL_haptic.c
@@ -25,7 +25,7 @@
 #include "../joystick/SDL_joystick_c.h" /* For SDL_PrivateJoystickValid */
 #include "SDL_assert.h"
 
-SDL_Haptic *SDL_haptics = NULL;
+static SDL_Haptic *SDL_haptics = NULL;
 
 
 /*
diff --git a/src/haptic/SDL_syshaptic.h b/src/haptic/SDL_syshaptic.h
index 372cefacf..a71d3a096 100644
--- a/src/haptic/SDL_syshaptic.h
+++ b/src/haptic/SDL_syshaptic.h
@@ -62,7 +62,7 @@ struct _SDL_Haptic
 extern int SDL_SYS_HapticInit(void);
 
 /* Function to return the number of haptic devices plugged in right now */
-extern int SDL_SYS_NumHaptics();
+extern int SDL_SYS_NumHaptics(void);
 
 /*
  * Gets the device dependent name of the haptic device
diff --git a/src/joystick/SDL_gamecontroller.c b/src/joystick/SDL_gamecontroller.c
index 7b69b4ac5..2f32a3263 100644
--- a/src/joystick/SDL_gamecontroller.c
+++ b/src/joystick/SDL_gamecontroller.c
@@ -146,7 +146,7 @@ static void UpdateEventsForDeviceRemoval()
 /*
  * Event filter to fire controller events from joystick ones
  */
-int SDL_GameControllerEventWatcher(void *userdata, SDL_Event * event)
+static int SDL_GameControllerEventWatcher(void *userdata, SDL_Event * event)
 {
     switch(event->type) {
     case SDL_JOYAXISMOTION:
@@ -291,7 +291,7 @@ int SDL_GameControllerEventWatcher(void *userdata, SDL_Event * event)
 /*
  * Helper function to scan the mappings database for a controller with the specified GUID
  */
-ControllerMapping_t *SDL_PrivateGetControllerMappingForGUID(SDL_JoystickGUID *guid)
+static ControllerMapping_t *SDL_PrivateGetControllerMappingForGUID(SDL_JoystickGUID *guid)
 {
     ControllerMapping_t *pSupportedController = s_pSupportedControllers;
     while (pSupportedController) {
@@ -389,7 +389,7 @@ const char* SDL_GameControllerGetStringForButton(SDL_GameControllerButton axis)
 /*
  * given a controller button name and a joystick name update our mapping structure with it
  */
-void SDL_PrivateGameControllerParseButton(const char *szGameButton, const char *szJoystickButton, struct _SDL_ControllerMapping *pMapping)
+static void SDL_PrivateGameControllerParseButton(const char *szGameButton, const char *szJoystickButton, struct _SDL_ControllerMapping *pMapping)
 {
     int iSDLButton = 0;
     SDL_GameControllerButton button;
@@ -502,7 +502,7 @@ SDL_PrivateGameControllerParseControllerConfigString(struct _SDL_ControllerMappi
 /*
  * Make a new button mapping struct
  */
-void SDL_PrivateLoadButtonMapping(struct _SDL_ControllerMapping *pMapping, SDL_JoystickGUID guid, const char *pchName, const char *pchMapping)
+static void SDL_PrivateLoadButtonMapping(struct _SDL_ControllerMapping *pMapping, SDL_JoystickGUID guid, const char *pchName, const char *pchMapping)
 {
     int j;
 
@@ -538,7 +538,7 @@ void SDL_PrivateLoadButtonMapping(struct _SDL_ControllerMapping *pMapping, SDL_J
 /*
  * grab the guid string from a mapping string
  */
-char *SDL_PrivateGetControllerGUIDFromMappingString(const char *pMapping)
+static char *SDL_PrivateGetControllerGUIDFromMappingString(const char *pMapping)
 {
     const char *pFirstComma = SDL_strchr(pMapping, ',');
     if (pFirstComma) {
@@ -577,7 +577,7 @@ char *SDL_PrivateGetControllerGUIDFromMappingString(const char *pMapping)
 /*
  * grab the name string from a mapping string
  */
-char *SDL_PrivateGetControllerNameFromMappingString(const char *pMapping)
+static char *SDL_PrivateGetControllerNameFromMappingString(const char *pMapping)
 {
     const char *pFirstComma, *pSecondComma;
     char *pchName;
@@ -604,7 +604,7 @@ char *SDL_PrivateGetControllerNameFromMappingString(const char *pMapping)
 /*
  * grab the button mapping string from a mapping string
  */
-char *SDL_PrivateGetControllerMappingFromMappingString(const char *pMapping)
+static char *SDL_PrivateGetControllerMappingFromMappingString(const char *pMapping)
 {
     const char *pFirstComma, *pSecondComma;
 
@@ -622,7 +622,7 @@ char *SDL_PrivateGetControllerMappingFromMappingString(const char *pMapping)
 /*
  * Helper function to refresh a mapping
  */
-void SDL_PrivateGameControllerRefreshMapping(ControllerMapping_t *pControllerMapping)
+static void SDL_PrivateGameControllerRefreshMapping(ControllerMapping_t *pControllerMapping)
 {
     SDL_GameController *gamecontrollerlist = SDL_gamecontrollers;
     while (gamecontrollerlist) {
@@ -699,7 +699,7 @@ SDL_PrivateAddMappingForGUID(SDL_JoystickGUID jGUID, const char *mappingString,
 /*
  * Helper function to determine pre-calculated offset to certain joystick mappings
  */
-ControllerMapping_t *SDL_PrivateGetControllerMapping(int device_index)
+static ControllerMapping_t *SDL_PrivateGetControllerMapping(int device_index)
 {
     SDL_JoystickGUID jGUID = SDL_JoystickGetDeviceGUID(device_index);
     ControllerMapping_t *mapping;
diff --git a/src/joystick/SDL_sysjoystick.h b/src/joystick/SDL_sysjoystick.h
index f4cad05ec..0d6d28c14 100644
--- a/src/joystick/SDL_sysjoystick.h
+++ b/src/joystick/SDL_sysjoystick.h
@@ -67,10 +67,10 @@ struct _SDL_Joystick
 extern int SDL_SYS_JoystickInit(void);
 
 /* Function to return the number of joystick devices plugged in right now */
-extern int SDL_SYS_NumJoysticks();
+extern int SDL_SYS_NumJoysticks(void);
 
 /* Function to cause any queued joystick insertions to be processed */
-extern void SDL_SYS_JoystickDetect();
+extern void SDL_SYS_JoystickDetect(void);
 
 /* Function to get the device-dependent name of a joystick */
 extern const char *SDL_SYS_JoystickNameForDeviceIndex(int device_index);
diff --git a/src/joystick/linux/SDL_sysjoystick.c b/src/joystick/linux/SDL_sysjoystick.c
index 38a53e190..e4f01a33d 100644
--- a/src/joystick/linux/SDL_sysjoystick.c
+++ b/src/joystick/linux/SDL_sysjoystick.c
@@ -282,6 +282,7 @@ MaybeRemoveDevice(const char *path)
 }
 #endif
 
+#if ! SDL_USE_LIBUDEV
 static int
 JoystickInitWithoutUdev(void)
 {
@@ -298,7 +299,7 @@ JoystickInitWithoutUdev(void)
 
     return numjoysticks;
 }
-
+#endif
 
 #if SDL_USE_LIBUDEV
 static int
@@ -342,9 +343,9 @@ SDL_SYS_JoystickInit(void)
 
 #if SDL_USE_LIBUDEV
     return JoystickInitWithUdev();
-#endif
-
+#else 
     return JoystickInitWithoutUdev();
+#endif
 }
 
 int SDL_SYS_NumJoysticks()
diff --git a/src/power/SDL_power.c b/src/power/SDL_power.c
index 016013b97..d559ac273 100644
--- a/src/power/SDL_power.c
+++ b/src/power/SDL_power.c
@@ -20,6 +20,7 @@
 */
 #include "../SDL_internal.h"
 #include "SDL_power.h"
+#include "SDL_syspower.h"
 
 /*
  * Returns SDL_TRUE if we have a definitive answer.
@@ -29,18 +30,6 @@ typedef SDL_bool
     (*SDL_GetPowerInfo_Impl) (SDL_PowerState * state, int *seconds,
                               int *percent);
 
-SDL_bool SDL_GetPowerInfo_Linux_sys_class_power_supply(SDL_PowerState *, int *, int *);
-SDL_bool SDL_GetPowerInfo_Linux_proc_acpi(SDL_PowerState *, int *, int *);
-SDL_bool SDL_GetPowerInfo_Linux_proc_apm(SDL_PowerState *, int *, int *);
-SDL_bool SDL_GetPowerInfo_Windows(SDL_PowerState *, int *, int *);
-SDL_bool SDL_GetPowerInfo_MacOSX(SDL_PowerState *, int *, int *);
-SDL_bool SDL_GetPowerInfo_Haiku(SDL_PowerState *, int *, int *);
-SDL_bool SDL_GetPowerInfo_UIKit(SDL_PowerState *, int *, int *);
-SDL_bool SDL_GetPowerInfo_Android(SDL_PowerState *, int *, int *);
-SDL_bool SDL_GetPowerInfo_PSP(SDL_PowerState *, int *, int *);
-SDL_bool SDL_GetPowerInfo_WinRT(SDL_PowerState *, int *, int *);
-SDL_bool SDL_GetPowerInfo_Emscripten(SDL_PowerState *, int *, int *);
-
 #ifndef SDL_POWER_DISABLED
 #ifdef SDL_POWER_HARDWIRED
 /* This is for things that _never_ have a battery */
diff --git a/src/power/SDL_syspower.h b/src/power/SDL_syspower.h
new file mode 100644
index 000000000..70b883d60
--- /dev/null
+++ b/src/power/SDL_syspower.h
@@ -0,0 +1,68 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+#include "../SDL_internal.h"
+
+/* These are functions that need to be implemented by a port of SDL */
+
+#ifndef _SDL_syspower_h
+#define _SDL_syspower_h
+
+#include "SDL_power.h"
+
+#ifndef SDL_POWER_DISABLED
+#ifdef SDL_POWER_LINUX          /* in order of preference. More than could work. */
+SDL_bool SDL_GetPowerInfo_Linux_sys_class_power_supply(SDL_PowerState *, int *, int *);
+SDL_bool SDL_GetPowerInfo_Linux_proc_acpi(SDL_PowerState *, int *, int *);
+SDL_bool SDL_GetPowerInfo_Linux_proc_apm(SDL_PowerState *, int *, int *);
+#endif
+#ifdef SDL_POWER_WINDOWS        /* handles Win32, Win64, PocketPC. */
+SDL_bool SDL_GetPowerInfo_Windows(SDL_PowerState *, int *, int *);
+#endif
+#ifdef SDL_POWER_UIKIT          /* handles iPhone/iPad/etc */
+SDL_bool SDL_GetPowerInfo_UIKit(SDL_PowerState *, int *, int *);
+#endif
+#ifdef SDL_POWER_MACOSX         /* handles Mac OS X, Darwin. */
+SDL_bool SDL_GetPowerInfo_MacOSX(SDL_PowerState *, int *, int *);
+#endif
+#ifdef SDL_POWER_HAIKU          /* with BeOS euc.jp apm driver. Does this work on Haiku? */
+SDL_bool SDL_GetPowerInfo_Haiku(SDL_PowerState *, int *, int *);
+#endif
+#ifdef SDL_POWER_ANDROID        /* handles Android. */
+SDL_bool SDL_GetPowerInfo_Android(SDL_PowerState *, int *, int *);
+#endif
+#ifdef SDL_POWER_PSP        /* handles PSP. */
+SDL_bool SDL_GetPowerInfo_PSP(SDL_PowerState *, int *, int *);
+#endif
+#ifdef SDL_POWER_WINRT          /* handles WinRT */
+SDL_bool SDL_GetPowerInfo_WinRT(SDL_PowerState *, int *, int *);
+#endif
+#ifdef SDL_POWER_EMSCRIPTEN     /* handles Emscripten */
+SDL_bool SDL_GetPowerInfo_Emscripten(SDL_PowerState *, int *, int *);
+#endif
+
+#ifdef SDL_POWER_HARDWIRED
+SDL_bool SDL_GetPowerInfo_Hardwired(SDL_PowerState *, int *, int *);
+#endif
+#endif
+
+#endif /* _SDL_syspower_h */
+
+/* vi: set ts=4 sw=4 expandtab: */
diff --git a/src/power/linux/SDL_syspower.c b/src/power/linux/SDL_syspower.c
index 793e26669..c25b449df 100644
--- a/src/power/linux/SDL_syspower.c
+++ b/src/power/linux/SDL_syspower.c
@@ -32,6 +32,7 @@
 #include <fcntl.h>
 
 #include "SDL_power.h"
+#include "../SDL_syspower.h"
 
 static const char *proc_apm_path = "/proc/apm";
 static const char *proc_acpi_battery_path = "/proc/acpi/battery";
diff --git a/src/render/opengl/SDL_shaders_gl.h b/src/render/opengl/SDL_shaders_gl.h
index 261627cc7..0b7d8ae48 100644
--- a/src/render/opengl/SDL_shaders_gl.h
+++ b/src/render/opengl/SDL_shaders_gl.h
@@ -34,7 +34,7 @@ typedef enum {
 
 typedef struct GL_ShaderContext GL_ShaderContext;
 
-extern GL_ShaderContext * GL_CreateShaderContext();
+extern GL_ShaderContext * GL_CreateShaderContext(void);
 extern void GL_SelectShader(GL_ShaderContext *ctx, GL_Shader shader);
 extern void GL_DestroyShaderContext(GL_ShaderContext *ctx);
 
diff --git a/src/render/opengles/SDL_render_gles.c b/src/render/opengles/SDL_render_gles.c
index 71f5b3a7a..fbed503cd 100644
--- a/src/render/opengles/SDL_render_gles.c
+++ b/src/render/opengles/SDL_render_gles.c
@@ -214,7 +214,7 @@ static int GLES_LoadFunctions(GLES_RenderData * data)
 
 static SDL_GLContext SDL_CurrentContext = NULL;
 
-GLES_FBOList *
+static GLES_FBOList *
 GLES_GetFBO(GLES_RenderData *data, Uint32 w, Uint32 h)
 {
    GLES_FBOList *result = data->framebuffers;
diff --git a/src/render/opengles2/SDL_render_gles2.c b/src/render/opengles2/SDL_render_gles2.c
index c846a7b39..f956bd142 100644
--- a/src/render/opengles2/SDL_render_gles2.c
+++ b/src/render/opengles2/SDL_render_gles2.c
@@ -307,7 +307,7 @@ static int GLES2_LoadFunctions(GLES2_DriverContext * data)
     return 0;
 }
 
-GLES2_FBOList *
+static GLES2_FBOList *
 GLES2_GetFBO(GLES2_DriverContext *data, Uint32 w, Uint32 h)
 {
    GLES2_FBOList *result = data->framebuffers;
@@ -1923,7 +1923,9 @@ static int GLES2_UnbindTexture (SDL_Renderer * renderer, SDL_Texture *texture)
  * Renderer instantiation                                                                        *
  *************************************************************************************************/
 
+#ifdef ZUNE_HD
 #define GL_NVIDIA_PLATFORM_BINARY_NV 0x890B
+#endif
 
 static void
 GLES2_ResetState(SDL_Renderer *renderer)
@@ -1963,7 +1965,7 @@ GLES2_CreateRenderer(SDL_Window *window, Uint32 flags)
 #ifndef ZUNE_HD
     GLboolean hasCompiler;
 #endif
-    Uint32 window_flags;
+    Uint32 window_flags = 0; /* -Wconditional-uninitialized */
     GLint window_framebuffer;
     GLint value;
     int profile_mask = 0, major = 0, minor = 0;
diff --git a/src/render/software/SDL_blendfillrect.c b/src/render/software/SDL_blendfillrect.c
index 7cfb274ae..74dadbd20 100644
--- a/src/render/software/SDL_blendfillrect.c
+++ b/src/render/software/SDL_blendfillrect.c
@@ -245,7 +245,7 @@ SDL_BlendFillRect(SDL_Surface * dst, const SDL_Rect * rect,
             } else {
                 return SDL_BlendFillRect_ARGB8888(dst, rect, blendMode, r, g, b, a);
             }
-            break;
+            /* break; -Wunreachable-code-break */
         }
         break;
     default:
diff --git a/src/render/software/SDL_blendline.c b/src/render/software/SDL_blendline.c
index ef0d58531..d7d0f6953 100644
--- a/src/render/software/SDL_blendline.c
+++ b/src/render/software/SDL_blendline.c
@@ -685,7 +685,7 @@ SDL_CalculateBlendLineFunc(const SDL_PixelFormat * fmt)
         } else {
             return SDL_BlendLine_RGB2;
         }
-        break;
+        /* break; -Wunreachable-code-break */
     case 4:
         if (fmt->Rmask == 0x00FF0000) {
             if (fmt->Amask) {
diff --git a/src/render/software/SDL_blendpoint.c b/src/render/software/SDL_blendpoint.c
index fc42dfe76..7c919dd8b 100644
--- a/src/render/software/SDL_blendpoint.c
+++ b/src/render/software/SDL_blendpoint.c
@@ -235,13 +235,11 @@ SDL_BlendPoint(SDL_Surface * dst, int x, int y, SDL_BlendMode blendMode, Uint8 r
         switch (dst->format->Rmask) {
         case 0x00FF0000:
             if (!dst->format->Amask) {
-                return SDL_BlendPoint_RGB888(dst, x, y, blendMode, r, g, b,
-                                             a);
+                return SDL_BlendPoint_RGB888(dst, x, y, blendMode, r, g, b, a);
             } else {
-                return SDL_BlendPoint_ARGB8888(dst, x, y, blendMode, r, g, b,
-                                               a);
+                return SDL_BlendPoint_ARGB8888(dst, x, y, blendMode, r, g, b, a);
             }
-            break;
+            /* break; -Wunreachable-code-break */
         }
         break;
     default:
diff --git a/src/render/software/SDL_rotate.c b/src/render/software/SDL_rotate.c
index 29168a986..5c899c346 100644
--- a/src/render/software/SDL_rotate.c
+++ b/src/render/software/SDL_rotate.c
@@ -79,7 +79,7 @@ to a situation where the program can segfault.
 /* !
 \brief Lower limit of absolute zoom factor or rotation degrees.
 */
-#define VALUE_LIMIT 0.001
+/* #define VALUE_LIMIT 0.001 */
 
 /* !
 \brief Returns colorkey info for a surface
diff --git a/src/stdlib/SDL_string.c b/src/stdlib/SDL_string.c
index 3e856b5f7..9198cfeaf 100644
--- a/src/stdlib/SDL_string.c
+++ b/src/stdlib/SDL_string.c
@@ -28,9 +28,10 @@
 
 #include "SDL_stdinc.h"
 
-
+#if !defined(HAVE_VSSCANF) || !defined(HAVE_STRTOL) || !defined(HAVE_STRTOUL)  || !defined(HAVE_STRTOLL) || !defined(HAVE_STRTOULL) || !defined(HAVE_STRTOD)
 #define SDL_isupperhex(X)   (((X) >= 'A') && ((X) <= 'F'))
 #define SDL_islowerhex(X)   (((X) >= 'a') && ((X) <= 'f'))
+#endif
 
 #define UTF8_IsLeadByte(c) ((c) >= 0xC0 && (c) <= 0xF4)
 #define UTF8_IsTrailingByte(c) ((c) >= 0x80 && (c) <= 0xBF)
diff --git a/src/test/SDL_test_crc32.c b/src/test/SDL_test_crc32.c
index 6e1220881..6d5715a3e 100644
--- a/src/test/SDL_test_crc32.c
+++ b/src/test/SDL_test_crc32.c
@@ -69,7 +69,7 @@ int SDLTest_Crc32Init(SDLTest_Crc32Context *crcContext)
 }
 
 /* Complete CRC32 calculation on a memory block */
-
+/* un-used
 int SDLTest_Crc32Calc(SDLTest_Crc32Context * crcContext, CrcUint8 *inBuf, CrcUint32 inLen, CrcUint32 *crc32)
 {
   if (SDLTest_Crc32CalcStart(crcContext,crc32)) {
@@ -86,6 +86,7 @@ int SDLTest_Crc32Calc(SDLTest_Crc32Context * crcContext, CrcUint8 *inBuf, CrcUin
 
   return 0;
 }
+*/
 
 /* Start crc calculation */
 
diff --git a/src/test/SDL_test_fuzzer.c b/src/test/SDL_test_fuzzer.c
index 9ae653643..0aeb79f05 100644
--- a/src/test/SDL_test_fuzzer.c
+++ b/src/test/SDL_test_fuzzer.c
@@ -196,7 +196,7 @@ SDLTest_RandomIntegerInRange(Sint32 pMin, Sint32 pMax)
  *
  * \returns Returns a random boundary value for the domain or 0 in case of error
  */
-Uint64
+static Uint64
 SDLTest_GenerateUnsignedBoundaryValues(const Uint64 maxValue, Uint64 boundary1, Uint64 boundary2, SDL_bool validDomain)
 {
         Uint64 b1, b2;
@@ -328,7 +328,7 @@ SDLTest_RandomUint64BoundaryValue(Uint64 boundary1, Uint64 boundary2, SDL_bool v
  *
  * \returns Returns a random boundary value for the domain or 0 in case of error
  */
-Sint64
+static Sint64
 SDLTest_GenerateSignedBoundaryValues(const Sint64 minValue, const Sint64 maxValue, Sint64 boundary1, Sint64 boundary2, SDL_bool validDomain)
 {
         Sint64 b1, b2;
diff --git a/src/test/SDL_test_harness.c b/src/test/SDL_test_harness.c
index 4b86c7a0d..748158228 100644
--- a/src/test/SDL_test_harness.c
+++ b/src/test/SDL_test_harness.c
@@ -50,7 +50,7 @@ static Uint32 SDLTest_TestCaseTimeout = 3600;
 *
 * \returns The generated seed string
 */
-char *
+static char *
 SDLTest_GenerateRunSeed(const int length)
 {
     char *seed = NULL;
@@ -97,8 +97,8 @@ SDLTest_GenerateRunSeed(const int length)
 * \returns The generated execution key to initialize the fuzzer with.
 *
 */
-Uint64
-SDLTest_GenerateExecKey(char *runSeed, char *suiteName, char *testName, int iteration)
+static Uint64
+SDLTest_GenerateExecKey(const char *runSeed, char *suiteName, char *testName, int iteration)
 {
     SDLTest_Md5Context md5Context;
     Uint64 *keys;
@@ -168,7 +168,7 @@ SDLTest_GenerateExecKey(char *runSeed, char *suiteName, char *testName, int iter
 *
 * \return Timer id or -1 on failure.
 */
-SDL_TimerID
+static SDL_TimerID
 SDLTest_SetTestTimeout(int timeout, void (*callback)())
 {
     Uint32 timeoutInMilliseconds;
@@ -206,8 +206,8 @@ SDLTest_SetTestTimeout(int timeout, void (*callback)())
 /**
 * \brief Timeout handler. Aborts test run and exits harness process.
 */
-void
-    SDLTest_BailOut()
+static void
+SDLTest_BailOut()
 {
     SDLTest_LogError("TestCaseTimeout timer expired. Aborting test run.");
     exit(TEST_ABORTED); /* bail out from the test */
@@ -223,8 +223,8 @@ void
 *
 * \returns Test case result.
 */
-int
-SDLTest_RunTest(SDLTest_TestSuiteReference *testSuite, SDLTest_TestCaseReference *testCase, Uint64 execKey, SDL_bool forceTestRun)
+static int
+SDLTest_RunTest(SDLTest_TestSuiteReference *testSuite, const SDLTest_TestCaseReference *testCase, Uint64 execKey, SDL_bool forceTestRun)
 {
     SDL_TimerID timer = 0;
     int testCaseResult = 0;
@@ -313,7 +313,8 @@ SDLTest_RunTest(SDLTest_TestSuiteReference *testSuite, SDLTest_TestCaseReference
 }
 
 /* Prints summary of all suites/tests contained in the given reference */
-void SDLTest_LogTestSuiteSummary(SDLTest_TestSuiteReference *testSuites)
+#if 0 
+static void SDLTest_LogTestSuiteSummary(SDLTest_TestSuiteReference *testSuites)
 {
     int suiteCounter;
     int testCounter;
@@ -340,12 +341,13 @@ void SDLTest_LogTestSuiteSummary(SDLTest_TestSuiteReference *testSuites)
         }
     }
 }
+#endif
 
 /* Gets a timer value in seconds */
-float GetClock()
+static float GetClock()
 {
-    float currentClock = (float)clock();
-    return currentClock / (float)CLOCKS_PER_SEC;
+    float currentClock = clock() / (float) CLOCKS_PER_SEC;
+    return currentClock;
 }
 
 /**
@@ -370,7 +372,7 @@ int SDLTest_RunSuites(SDLTest_TestSuiteReference *testSuites[], const char *user
     int testCounter;
     int iterationCounter;
     SDLTest_TestSuiteReference *testSuite;
-    SDLTest_TestCaseReference *testCase;
+    const SDLTest_TestCaseReference *testCase;
     const char *runSeed = NULL;
     char *currentSuiteName;
     char *currentTestName;
@@ -396,7 +398,7 @@ int SDLTest_RunSuites(SDLTest_TestSuiteReference *testSuites[], const char *user
     Uint32 testPassedCount = 0;
     Uint32 testSkippedCount = 0;
     Uint32 countSum = 0;
-    SDLTest_TestCaseReference **failedTests;
+    const SDLTest_TestCaseReference **failedTests;
 
     /* Sanitize test iterations */
     if (testIterations < 1) {
@@ -440,7 +442,7 @@ int SDLTest_RunSuites(SDLTest_TestSuiteReference *testSuites[], const char *user
 	}
 
 	/* Pre-allocate an array for tracking failed tests (potentially all test cases) */
-	failedTests = (SDLTest_TestCaseReference **)SDL_malloc(totalNumberOfTests * sizeof(SDLTest_TestCaseReference *));
+	failedTests = (const SDLTest_TestCaseReference **)SDL_malloc(totalNumberOfTests * sizeof(SDLTest_TestCaseReference *));
 	if (failedTests == NULL) {	
 	   SDLTest_LogError("Unable to allocate cache for failed tests");
            SDL_Error(SDL_ENOMEM);	   
@@ -466,7 +468,7 @@ int SDLTest_RunSuites(SDLTest_TestSuiteReference *testSuites[], const char *user
             testCounter = 0;
             while (testSuite->testCases[testCounter] && testFilter == 0)
             {
-                testCase=(SDLTest_TestCaseReference *)testSuite->testCases[testCounter];
+                testCase = testSuite->testCases[testCounter];
                 testCounter++;
                 if (testCase->name != NULL && SDL_strcmp(filter, testCase->name) == 0) {
                     /* Matched a test name */
@@ -521,7 +523,7 @@ int SDLTest_RunSuites(SDLTest_TestSuiteReference *testSuites[], const char *user
             testCounter = 0;
             while(testSuite->testCases[testCounter])
             {
-                testCase=(SDLTest_TestCaseReference *)testSuite->testCases[testCounter];
+                testCase = testSuite->testCases[testCounter];
                 currentTestName = (char *)((testCase->name) ? testCase->name : SDLTEST_INVALID_NAME_FORMAT);
                 testCounter++;
 
@@ -562,7 +564,7 @@ int SDLTest_RunSuites(SDLTest_TestSuiteReference *testSuites[], const char *user
                         if (userExecKey != 0) {
                             execKey = userExecKey;
                         } else {
-                            execKey = SDLTest_GenerateExecKey((char *)runSeed, testSuite->name, testCase->name, iterationCounter);
+                            execKey = SDLTest_GenerateExecKey(runSeed, testSuite->name, testCase->name, iterationCounter);
                         }
 
                         SDLTest_Log("Test Iteration %i: execKey %" SDL_PRIu64, iterationCounter, execKey);
diff --git a/src/test/SDL_test_imageBlit.c b/src/test/SDL_test_imageBlit.c
index 5896ca099..9cca2d985 100644
--- a/src/test/SDL_test_imageBlit.c
+++ b/src/test/SDL_test_imageBlit.c
@@ -24,7 +24,7 @@
 
 /* GIMP RGB C-Source image dump (blit.c) */
 
-const SDLTest_SurfaceImage_t SDLTest_imageBlit = {
+static const SDLTest_SurfaceImage_t SDLTest_imageBlit = {
   80, 60, 3,
   "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"
   "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"
@@ -561,7 +561,7 @@ SDL_Surface *SDLTest_ImageBlit()
    return surface;
 }
 
-const SDLTest_SurfaceImage_t SDLTest_imageBlitColor = {
+static const SDLTest_SurfaceImage_t SDLTest_imageBlitColor = {
   80, 60, 3,
   "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"
   "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"
@@ -1044,7 +1044,7 @@ SDL_Surface *SDLTest_ImageBlitColor()
    return surface;
 }
 
-const SDLTest_SurfaceImage_t SDLTest_imageBlitAlpha = {
+static const SDLTest_SurfaceImage_t SDLTest_imageBlitAlpha = {
   80, 60, 3,
   "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"
   "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"
diff --git a/src/test/SDL_test_imageBlitBlend.c b/src/test/SDL_test_imageBlitBlend.c
index 6e8c2f1b4..3ee8445cf 100644
--- a/src/test/SDL_test_imageBlitBlend.c
+++ b/src/test/SDL_test_imageBlitBlend.c
@@ -24,7 +24,7 @@
 
 /* GIMP RGB C-Source image dump (alpha.c) */
 
-const SDLTest_SurfaceImage_t SDLTest_imageBlitBlendAdd = {
+static const SDLTest_SurfaceImage_t SDLTest_imageBlitBlendAdd = {
   80, 60, 3,
   "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"
   "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"
@@ -601,7 +601,7 @@ SDL_Surface *SDLTest_ImageBlitBlendAdd()
    return surface;
 }
 
-const SDLTest_SurfaceImage_t SDLTest_imageBlitBlend = {
+static const SDLTest_SurfaceImage_t SDLTest_imageBlitBlend = {
   80, 60, 3,
   "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"
   "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"
@@ -1131,7 +1131,7 @@ SDL_Surface *SDLTest_ImageBlitBlend()
    return surface;
 }
 
-const SDLTest_SurfaceImage_t SDLTest_imageBlitBlendMod = {
+static const SDLTest_SurfaceImage_t SDLTest_imageBlitBlendMod = {
   80, 60, 3,
   "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"
   "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"
@@ -1561,7 +1561,7 @@ SDL_Surface *SDLTest_ImageBlitBlendMod()
    return surface;
 }
 
-const SDLTest_SurfaceImage_t SDLTest_imageBlitBlendNone = {
+static const SDLTest_SurfaceImage_t SDLTest_imageBlitBlendNone = {
   80, 60, 3,
   "\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377"
   "\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377"
@@ -2374,7 +2374,7 @@ SDL_Surface *SDLTest_ImageBlitBlendNone()
    return surface;
 }
 
-const SDLTest_SurfaceImage_t SDLTest_imageBlitBlendAll = {
+static const SDLTest_SurfaceImage_t SDLTest_imageBlitBlendAll = {
   80, 60, 3,
   "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"
   "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"
diff --git a/src/test/SDL_test_imageFace.c b/src/test/SDL_test_imageFace.c
index 84f5037f4..4f13cd80a 100644
--- a/src/test/SDL_test_imageFace.c
+++ b/src/test/SDL_test_imageFace.c
@@ -24,7 +24,7 @@
 
 /* GIMP RGBA C-Source image dump (face.c) */
 
-const SDLTest_SurfaceImage_t SDLTest_imageFace = {
+static const SDLTest_SurfaceImage_t SDLTest_imageFace = {
   32, 32, 4,
   "\377\377\377\0\377\377\377\0\377\377\377\0\377\377\377\0\377\377\377\0\377"
   "\377\377\0\377\377\377\0\377\377\377\0\377\377\377\0\377\377\377\0\377\377"
diff --git a/src/test/SDL_test_imagePrimitives.c b/src/test/SDL_test_imagePrimitives.c
index 4ab48d2de..8d562cc3e 100644
--- a/src/test/SDL_test_imagePrimitives.c
+++ b/src/test/SDL_test_imagePrimitives.c
@@ -24,7 +24,7 @@
 
 /* GIMP RGB C-Source image dump (primitives.c) */
 
-const SDLTest_SurfaceImage_t SDLTest_imagePrimitives = {
+static const SDLTest_SurfaceImage_t SDLTest_imagePrimitives = {
   80, 60, 3,
   "\5ii\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"
   "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"
diff --git a/src/test/SDL_test_imagePrimitivesBlend.c b/src/test/SDL_test_imagePrimitivesBlend.c
index 5e538628e..21974166a 100644
--- a/src/test/SDL_test_imagePrimitivesBlend.c
+++ b/src/test/SDL_test_imagePrimitivesBlend.c
@@ -24,7 +24,7 @@
 
 /* GIMP RGB C-Source image dump (alpha.c) */
 
-const SDLTest_SurfaceImage_t SDLTest_imagePrimitivesBlend = {
+static const SDLTest_SurfaceImage_t SDLTest_imagePrimitivesBlend = {
   80, 60, 3,
   "\260e\15\222\356/\37\313\15\36\330\17K\3745D\3471\0\20\0D\3502D\3502<\321"
   ",\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\0-\0\377\377"
diff --git a/src/test/SDL_test_log.c b/src/test/SDL_test_log.c
index a2f857f26..a22b10f6b 100644
--- a/src/test/SDL_test_log.c
+++ b/src/test/SDL_test_log.c
@@ -50,7 +50,7 @@
  *
  * \return Ascii representation of the timestamp in localtime in the format '08/23/01 14:55:02'
  */
-char *SDLTest_TimestampToString(const time_t timestamp)
+static char *SDLTest_TimestampToString(const time_t timestamp)
 {
     time_t copy;
     static char buffer[64];
diff --git a/src/thread/SDL_systhread.h b/src/thread/SDL_systhread.h
index 05a012536..6d19427a3 100644
--- a/src/thread/SDL_systhread.h
+++ b/src/thread/SDL_systhread.h
@@ -55,7 +55,7 @@ extern void SDL_SYS_WaitThread(SDL_Thread * thread);
 extern void SDL_SYS_DetachThread(SDL_Thread * thread);
 
 /* Get the thread local storage for this thread */
-extern SDL_TLSData *SDL_SYS_GetTLSData();
+extern SDL_TLSData *SDL_SYS_GetTLSData(void);
 
 /* Set the thread local storage for this thread */
 extern int SDL_SYS_SetTLSData(SDL_TLSData *data);
diff --git a/src/thread/SDL_thread_c.h b/src/thread/SDL_thread_c.h
index 554325d6d..e1eb171b2 100644
--- a/src/thread/SDL_thread_c.h
+++ b/src/thread/SDL_thread_c.h
@@ -82,7 +82,7 @@ typedef struct {
    This is only intended as a fallback if getting real thread-local
    storage fails or isn't supported on this platform.
  */
-extern SDL_TLSData *SDL_Generic_GetTLSData();
+extern SDL_TLSData *SDL_Generic_GetTLSData(void);
 
 /* Set cross-platform, slow, thread local storage for this thread.
    This is only intended as a fallback if getting real thread-local
diff --git a/src/thread/pthread/SDL_syscond.c b/src/thread/pthread/SDL_syscond.c
index 998ac55b3..69790cbc1 100644
--- a/src/thread/pthread/SDL_syscond.c
+++ b/src/thread/pthread/SDL_syscond.c
@@ -129,7 +129,7 @@ SDL_CondWaitTimeout(SDL_cond * cond, SDL_mutex * mutex, Uint32 ms)
     switch (retval) {
     case EINTR:
         goto tryagain;
-        break;
+        /* break; -Wunreachable-code-break */
     case ETIMEDOUT:
         retval = SDL_MUTEX_TIMEDOUT;
         break;
diff --git a/src/thread/pthread/SDL_systls.c b/src/thread/pthread/SDL_systls.c
index 622ad0297..ba8503663 100644
--- a/src/thread/pthread/SDL_systls.c
+++ b/src/thread/pthread/SDL_systls.c
@@ -20,6 +20,7 @@
 */
 #include "../../SDL_internal.h"
 #include "SDL_thread.h"
+#include "../SDL_systhread.h"
 #include "../SDL_thread_c.h"
 
 #include <pthread.h>
diff --git a/src/timer/unix/SDL_systimer.c b/src/timer/unix/SDL_systimer.c
index 217fe327f..b3e8933e9 100644
--- a/src/timer/unix/SDL_systimer.c
+++ b/src/timer/unix/SDL_systimer.c
@@ -29,6 +29,7 @@
 
 #include "SDL_timer.h"
 #include "SDL_assert.h"
+#include "../SDL_timer_c.h"
 
 /* The clock_gettime provides monotonous time, so we should use it if
    it's available. The clock_gettime function is behind ifdef
diff --git a/src/video/SDL_RLEaccel.c b/src/video/SDL_RLEaccel.c
index 67baaf664..4f8b0e7fc 100644
--- a/src/video/SDL_RLEaccel.c
+++ b/src/video/SDL_RLEaccel.c
@@ -90,9 +90,11 @@
 #include "SDL_blit.h"
 #include "SDL_RLEaccel_c.h"
 
+/*
 #ifndef MAX
 #define MAX(a, b) ((a) > (b) ? (a) : (b))
 #endif
+*/
 #ifndef MIN
 #define MIN(a, b) ((a) < (b) ? (a) : (b))
 #endif
diff --git a/src/video/SDL_blit_1.c b/src/video/SDL_blit_1.c
index 69c15d08d..078d3fced 100644
--- a/src/video/SDL_blit_1.c
+++ b/src/video/SDL_blit_1.c
@@ -70,12 +70,14 @@ Blit1to1(SDL_BlitInfo * info)
 }
 
 /* This is now endian dependent */
-#if ( SDL_BYTEORDER == SDL_LIL_ENDIAN )
-#define HI	1
-#define LO	0
-#else /* ( SDL_BYTEORDER == SDL_BIG_ENDIAN ) */
-#define HI	0
-#define LO	1
+#ifndef USE_DUFFS_LOOP
+# if ( SDL_BYTEORDER == SDL_LIL_ENDIAN )
+#  define HI	1
+#  define LO	0
+# else /* ( SDL_BYTEORDER == SDL_BIG_ENDIAN ) */
+#  define HI	0
+#  define LO	1
+# endif
 #endif
 static void
 Blit1to2(SDL_BlitInfo * info)
diff --git a/src/video/SDL_bmp.c b/src/video/SDL_bmp.c
index 2d9cf240b..2cefcd1b5 100644
--- a/src/video/SDL_bmp.c
+++ b/src/video/SDL_bmp.c
@@ -43,8 +43,8 @@
 /* Compression encodings for BMP files */
 #ifndef BI_RGB
 #define BI_RGB      0
-#define BI_RLE8     1
-#define BI_RLE4     2
+/* #define BI_RLE8     1 */
+/* #define BI_RLE4     2 */
 #define BI_BITFIELDS    3
 #endif
 
diff --git a/src/video/SDL_video.c b/src/video/SDL_video.c
index 0a21ef5fc..b8d362e04 100644
--- a/src/video/SDL_video.c
+++ b/src/video/SDL_video.c
@@ -46,9 +46,11 @@
 #include "SDL_opengles2.h"
 #endif /* SDL_VIDEO_OPENGL_ES2 && !SDL_VIDEO_OPENGL */
 
+#if !SDL_VIDEO_OPENGL
 #ifndef GL_CONTEXT_RELEASE_BEHAVIOR_KHR
 #define GL_CONTEXT_RELEASE_BEHAVIOR_KHR 0x82FB
 #endif
+#endif
 
 /* On Windows, windows.h defines CreateWindow */
 #ifdef CreateWindow
@@ -3617,8 +3619,9 @@ SDL_IsScreenKeyboardShown(SDL_Window *window)
 #include "x11/SDL_x11messagebox.h"
 #endif
 
-// This function will be unused if none of the above video drivers are present.
-SDL_UNUSED static SDL_bool SDL_MessageboxValidForDriver(const SDL_MessageBoxData *messageboxdata, SDL_SYSWM_TYPE drivertype)
+
+#if SDL_VIDEO_DRIVER_WINDOWS || SDL_VIDEO_DRIVER_WINRT || SDL_VIDEO_DRIVER_COCOA || SDL_VIDEO_DRIVER_UIKIT || SDL_VIDEO_DRIVER_X11
+static SDL_bool SDL_MessageboxValidForDriver(const SDL_MessageBoxData *messageboxdata, SDL_SYSWM_TYPE drivertype)
 {
     SDL_SysWMinfo info;
     SDL_Window *window = messageboxdata->window;
@@ -3634,6 +3637,7 @@ SDL_UNUSED static SDL_bool SDL_MessageboxValidForDriver(const SDL_MessageBoxData
         return (info.subsystem == drivertype);
     }
 }
+#endif
 
 int
 SDL_ShowMessageBox(const SDL_MessageBoxData *messageboxdata, int *buttonid)
diff --git a/src/video/x11/SDL_x11events.c b/src/video/x11/SDL_x11events.c
index 8d7e99785..cefd43310 100644
--- a/src/video/x11/SDL_x11events.c
+++ b/src/video/x11/SDL_x11events.c
@@ -201,7 +201,7 @@ X11_IsWheelEvent(Display * display,XEvent * event,int * xticks,int * yticks)
 
    On error, -1 is returned.
  */
-int X11_URIDecode(char *buf, int len) {
+static int X11_URIDecode(char *buf, int len) {
     int ri, wi, di;
     char decode = '\0';
     if (buf == NULL || len < 0) {
diff --git a/src/video/x11/SDL_x11messagebox.c b/src/video/x11/SDL_x11messagebox.c
index fc8b1b26b..a0a4a405e 100644
--- a/src/video/x11/SDL_x11messagebox.c
+++ b/src/video/x11/SDL_x11messagebox.c
@@ -27,6 +27,7 @@
 #include "SDL_x11video.h"
 #include "SDL_x11dyn.h"
 #include "SDL_assert.h"
+#include "SDL_x11messagebox.h"
 
 #include <X11/keysym.h>
 #include <locale.h>
diff --git a/src/video/x11/SDL_x11modes.c b/src/video/x11/SDL_x11modes.c
index 29307b3a6..3749fb594 100644
--- a/src/video/x11/SDL_x11modes.c
+++ b/src/video/x11/SDL_x11modes.c
@@ -134,14 +134,14 @@ X11_GetPixelFormatFromVisualInfo(Display * display, XVisualInfo * vinfo)
             } else {
                 return SDL_PIXELFORMAT_INDEX4MSB;
             }
-            break;
+            /* break; -Wunreachable-code-break */
         case 1:
             if (BitmapBitOrder(display) == LSBFirst) {
                 return SDL_PIXELFORMAT_INDEX1LSB;
             } else {
                 return SDL_PIXELFORMAT_INDEX1MSB;
             }
-            break;
+            /* break; -Wunreachable-code-break */
         }
     }
 
@@ -149,7 +149,7 @@ X11_GetPixelFormatFromVisualInfo(Display * display, XVisualInfo * vinfo)
 }
 
 /* Global for the error handler */
-int vm_event, vm_error = -1;
+static int vm_event, vm_error = -1;
 
 #if SDL_VIDEO_DRIVER_X11_XINERAMA
 static SDL_bool
@@ -349,7 +349,7 @@ SetXRandRDisplayName(Display *dpy, Atom EDID, char *name, const size_t namelen,
 }
 
 
-int
+static int
 X11_InitModes_XRandR(_THIS)
 {
     SDL_VideoData *data = (SDL_VideoData *) _this->driverdata;
@@ -569,7 +569,7 @@ CalculateXVidModeRefreshRate(const XF86VidModeModeInfo * info)
                                                          info->vtotal)) : 0;
 }
 
-SDL_bool
+static SDL_bool
 SetXVidModeModeInfo(const XF86VidModeModeInfo *info, SDL_DisplayMode *mode)
 {
     mode->w = info->hdisplay;
@@ -584,7 +584,7 @@ int
 X11_InitModes(_THIS)
 {
     SDL_VideoData *data = (SDL_VideoData *) _this->driverdata;
-    int snum, screen, screencount;
+    int snum, screen, screencount = 0;
 #if SDL_VIDEO_DRIVER_X11_XINERAMA
     int xinerama_major, xinerama_minor;
     int use_xinerama = 0;
diff --git a/src/video/x11/SDL_x11opengl.c b/src/video/x11/SDL_x11opengl.c
index 3c73f8ba5..c29f71de8 100644
--- a/src/video/x11/SDL_x11opengl.c
+++ b/src/video/x11/SDL_x11opengl.c
@@ -519,6 +519,7 @@ X11_GL_GetVisual(_THIS, Display * display, int screen)
     return vinfo;
 }
 
+#if 0
 #ifndef GLXBadContext
 #define GLXBadContext 0
 #endif
@@ -528,6 +529,8 @@ X11_GL_GetVisual(_THIS, Display * display, int screen)
 #ifndef GLXBadProfileARB
 #define GLXBadProfileARB 13
 #endif
+#endif
+
 static int (*handler) (Display *, XErrorEvent *) = NULL;
 static const char *errorHandlerOperation = NULL;
 static int errorBase = 0;
diff --git a/src/video/x11/SDL_x11window.c b/src/video/x11/SDL_x11window.c
index 668bce225..7ed27baf8 100644
--- a/src/video/x11/SDL_x11window.c
+++ b/src/video/x11/SDL_x11window.c
@@ -44,7 +44,7 @@
 
 #define _NET_WM_STATE_REMOVE    0l
 #define _NET_WM_STATE_ADD       1l
-#define _NET_WM_STATE_TOGGLE    2l
+/* #define _NET_WM_STATE_TOGGLE    2l */
 
 static Bool isMapNotify(Display *dpy, XEvent *ev, XPointer win)
 {