diff --git a/include/SDL3/SDL_audio.h b/include/SDL3/SDL_audio.h
index a4afb62a8..1d308e4f6 100644
--- a/include/SDL3/SDL_audio.h
+++ b/include/SDL3/SDL_audio.h
@@ -801,6 +801,10 @@ extern DECLSPEC int SDLCALL SDL_FlushAudioStream(SDL_AudioStream *stream);
 /**
  * Clear any pending data in the stream without converting it
  *
+ * \param   stream The audio stream to clear
+ * \returns 0 on success or a negative error code on failure; call
+ *          SDL_GetError() for more information.
+ *
  * \since This function is available since SDL 3.0.0.
  *
  * \sa SDL_CreateAudioStream
@@ -810,7 +814,7 @@ extern DECLSPEC int SDLCALL SDL_FlushAudioStream(SDL_AudioStream *stream);
  * \sa SDL_FlushAudioStream
  * \sa SDL_DestroyAudioStream
  */
-extern DECLSPEC void SDLCALL SDL_ClearAudioStream(SDL_AudioStream *stream);
+extern DECLSPEC int SDLCALL SDL_ClearAudioStream(SDL_AudioStream *stream);
 
 /**
  * Free an audio stream
diff --git a/include/SDL3/SDL_gamepad.h b/include/SDL3/SDL_gamepad.h
index f9e0a0244..3f94d402e 100644
--- a/include/SDL3/SDL_gamepad.h
+++ b/include/SDL3/SDL_gamepad.h
@@ -537,10 +537,12 @@ extern DECLSPEC int SDLCALL SDL_GetGamepadPlayerIndex(SDL_Gamepad *gamepad);
  * \param gamepad the gamepad object to adjust.
  * \param player_index Player index to assign to this gamepad, or -1 to clear
  *                     the player index and turn off player LEDs.
+ * \returns 0 on success or a negative error code on failure; call
+ *          SDL_GetError() for more information.
  *
  * \since This function is available since SDL 3.0.0.
  */
-extern DECLSPEC void SDLCALL SDL_SetGamepadPlayerIndex(SDL_Gamepad *gamepad, int player_index);
+extern DECLSPEC int SDLCALL SDL_SetGamepadPlayerIndex(SDL_Gamepad *gamepad, int player_index);
 
 /**
  * Get the USB vendor ID of an opened gamepad, if available.
diff --git a/include/SDL3/SDL_guid.h b/include/SDL3/SDL_guid.h
index 62f5f70b4..11f1ffa6c 100644
--- a/include/SDL3/SDL_guid.h
+++ b/include/SDL3/SDL_guid.h
@@ -66,12 +66,14 @@ typedef struct {
  * \param guid the ::SDL_GUID you wish to convert to string
  * \param pszGUID buffer in which to write the ASCII string
  * \param cbGUID the size of pszGUID
+ * \returns 0 on success or a negative error code on failure; call
+ *          SDL_GetError() for more information.
  *
  * \since This function is available since SDL 3.0.0.
  *
  * \sa SDL_GUIDFromString
  */
-extern DECLSPEC void SDLCALL SDL_GUIDToString(SDL_GUID guid, char *pszGUID, int cbGUID);
+extern DECLSPEC int SDLCALL SDL_GUIDToString(SDL_GUID guid, char *pszGUID, int cbGUID);
 
 /**
  * Convert a GUID string into a ::SDL_GUID structure.
diff --git a/include/SDL3/SDL_joystick.h b/include/SDL3/SDL_joystick.h
index e17e3f936..0ef2235f1 100644
--- a/include/SDL3/SDL_joystick.h
+++ b/include/SDL3/SDL_joystick.h
@@ -597,6 +597,8 @@ extern DECLSPEC SDL_JoystickType SDLCALL SDL_GetJoystickType(SDL_Joystick *joyst
  * \param guid the SDL_JoystickGUID you wish to convert to string
  * \param pszGUID buffer in which to write the ASCII string
  * \param cbGUID the size of pszGUID
+ * \returns 0 on success or a negative error code on failure; call
+ *          SDL_GetError() for more information.
  *
  * \since This function is available since SDL 3.0.0.
  *
@@ -604,7 +606,7 @@ extern DECLSPEC SDL_JoystickType SDLCALL SDL_GetJoystickType(SDL_Joystick *joyst
  * \sa SDL_GetJoystickGUID
  * \sa SDL_GetJoystickGUIDFromString
  */
-extern DECLSPEC void SDLCALL SDL_GetJoystickGUIDString(SDL_JoystickGUID guid, char *pszGUID, int cbGUID);
+extern DECLSPEC int SDLCALL SDL_GetJoystickGUIDString(SDL_JoystickGUID guid, char *pszGUID, int cbGUID);
 
 /**
  * Convert a GUID string into a SDL_JoystickGUID structure.
diff --git a/include/SDL3/SDL_surface.h b/include/SDL3/SDL_surface.h
index 80cc1ca2f..beb969d14 100644
--- a/include/SDL3/SDL_surface.h
+++ b/include/SDL3/SDL_surface.h
@@ -529,13 +529,15 @@ extern DECLSPEC SDL_bool SDLCALL SDL_SetSurfaceClipRect(SDL_Surface *surface,
  *                clipped
  * \param rect an SDL_Rect structure filled in with the clipping rectangle for
  *             the surface
+ * \returns 0 on success or a negative error code on failure; call
+ *          SDL_GetError() for more information.
  *
  * \since This function is available since SDL 3.0.0.
  *
  * \sa SDL_BlitSurface
  * \sa SDL_SetSurfaceClipRect
  */
-extern DECLSPEC void SDLCALL SDL_GetSurfaceClipRect(SDL_Surface *surface,
+extern DECLSPEC int SDLCALL SDL_GetSurfaceClipRect(SDL_Surface *surface,
                                              SDL_Rect *rect);
 
 /*
diff --git a/include/SDL3/SDL_version.h b/include/SDL3/SDL_version.h
index 0d954d467..4f34f9487 100644
--- a/include/SDL3/SDL_version.h
+++ b/include/SDL3/SDL_version.h
@@ -115,12 +115,14 @@ typedef struct SDL_version
  * This function may be called safely at any time, even before SDL_Init().
  *
  * \param ver the SDL_version structure that contains the version information
+ * \returns 0 on success or a negative error code on failure; call
+ *          SDL_GetError() for more information.
  *
  * \since This function is available since SDL 3.0.0.
  *
  * \sa SDL_GetRevision
  */
-extern DECLSPEC void SDLCALL SDL_GetVersion(SDL_version * ver);
+extern DECLSPEC int SDLCALL SDL_GetVersion(SDL_version * ver);
 
 /**
  * Get the code revision of SDL that is linked against your program.
diff --git a/src/SDL.c b/src/SDL.c
index 9d1d9354a..0fe3bbb81 100644
--- a/src/SDL.c
+++ b/src/SDL.c
@@ -513,13 +513,13 @@ void SDL_Quit(void)
 }
 
 /* Get the library version number */
-void SDL_GetVersion(SDL_version *ver)
+int SDL_GetVersion(SDL_version *ver)
 {
     static SDL_bool check_hint = SDL_TRUE;
     static SDL_bool legacy_version = SDL_FALSE;
 
     if (ver == NULL) {
-        return;
+        return SDL_InvalidParamError("ver");
     }
 
     SDL_VERSION(ver);
@@ -534,6 +534,7 @@ void SDL_GetVersion(SDL_version *ver)
         ver->patch = ver->minor;
         ver->minor = 0;
     }
+    return 0;
 }
 
 /* Get the library source revision */
diff --git a/src/SDL_guid.c b/src/SDL_guid.c
index 7cc89d5ad..61387941c 100644
--- a/src/SDL_guid.c
+++ b/src/SDL_guid.c
@@ -21,13 +21,16 @@
 #include "SDL_internal.h"
 
 /* convert the guid to a printable string */
-void SDL_GUIDToString(SDL_GUID guid, char *pszGUID, int cbGUID)
+int SDL_GUIDToString(SDL_GUID guid, char *pszGUID, int cbGUID)
 {
     static const char k_rgchHexToASCII[] = "0123456789abcdef";
     int i;
 
-    if ((pszGUID == NULL) || (cbGUID <= 0)) {
-        return;
+    if (pszGUID == NULL) {
+        return SDL_InvalidParamError("pszGUID");
+    }
+    if (cbGUID <= 0) {
+        return SDL_InvalidParamError("cbGUID");
     }
 
     for (i = 0; i < sizeof(guid.data) && i < (cbGUID - 1) / 2; i++) {
@@ -39,6 +42,7 @@ void SDL_GUIDToString(SDL_GUID guid, char *pszGUID, int cbGUID)
         *pszGUID++ = k_rgchHexToASCII[c & 0x0F];
     }
     *pszGUID = '\0';
+    return 0;
 }
 
 /*-----------------------------------------------------------------------------
diff --git a/src/audio/SDL_audiocvt.c b/src/audio/SDL_audiocvt.c
index 895e9cf6a..af44d0a5c 100644
--- a/src/audio/SDL_audiocvt.c
+++ b/src/audio/SDL_audiocvt.c
@@ -1470,10 +1470,10 @@ int SDL_GetAudioStreamAvailable(SDL_AudioStream *stream)
     return stream ? (int)SDL_GetDataQueueSize(stream->queue) : 0;
 }
 
-void SDL_ClearAudioStream(SDL_AudioStream *stream)
+int SDL_ClearAudioStream(SDL_AudioStream *stream)
 {
     if (stream == NULL) {
-        SDL_InvalidParamError("stream");
+        return SDL_InvalidParamError("stream");
     } else {
         SDL_ClearDataQueue(stream->queue, (size_t)stream->packetlen * 2);
         if (stream->reset_resampler_func) {
@@ -1481,6 +1481,7 @@ void SDL_ClearAudioStream(SDL_AudioStream *stream)
         }
         stream->first_run = SDL_TRUE;
         stream->staging_buffer_filled = 0;
+        return 0;
     }
 }
 
diff --git a/src/dynapi/SDL_dynapi_procs.h b/src/dynapi/SDL_dynapi_procs.h
index 2363ae002..9cab0d0ac 100644
--- a/src/dynapi/SDL_dynapi_procs.h
+++ b/src/dynapi/SDL_dynapi_procs.h
@@ -139,7 +139,7 @@ SDL_DYNAPI_PROC(int,SDL_BlitSurfaceScaled,(SDL_Surface *a, const SDL_Rect *b, SD
 SDL_DYNAPI_PROC(int,SDL_BlitSurfaceUnchecked,(SDL_Surface *a, SDL_Rect *b, SDL_Surface *c, SDL_Rect *d),(a,b,c,d),return)
 SDL_DYNAPI_PROC(int,SDL_BlitSurfaceUncheckedScaled,(SDL_Surface *a, SDL_Rect *b, SDL_Surface *c, SDL_Rect *d),(a,b,c,d),return)
 SDL_DYNAPI_PROC(int,SDL_CaptureMouse,(SDL_bool a),(a),return)
-SDL_DYNAPI_PROC(void,SDL_ClearAudioStream,(SDL_AudioStream *a),(a),)
+SDL_DYNAPI_PROC(int,SDL_ClearAudioStream,(SDL_AudioStream *a),(a),return)
 SDL_DYNAPI_PROC(void,SDL_ClearComposition,(void),(),)
 SDL_DYNAPI_PROC(void,SDL_ClearError,(void),(),)
 SDL_DYNAPI_PROC(void,SDL_ClearHints,(void),(),)
@@ -230,7 +230,7 @@ SDL_DYNAPI_PROC(int,SDL_GL_SwapWindow,(SDL_Window *a),(a),return)
 SDL_DYNAPI_PROC(int,SDL_GL_UnbindTexture,(SDL_Texture *a),(a),return)
 SDL_DYNAPI_PROC(void,SDL_GL_UnloadLibrary,(void),(),)
 SDL_DYNAPI_PROC(SDL_GUID,SDL_GUIDFromString,(const char *a),(a),return)
-SDL_DYNAPI_PROC(void,SDL_GUIDToString,(SDL_GUID a, char *b, int c),(a,b,c),)
+SDL_DYNAPI_PROC(int,SDL_GUIDToString,(SDL_GUID a, char *b, int c),(a,b,c),return)
 SDL_DYNAPI_PROC(SDL_bool,SDL_GamepadConnected,(SDL_Gamepad *a),(a),return)
 SDL_DYNAPI_PROC(SDL_bool,SDL_GamepadEventsEnabled,(void),(),return)
 SDL_DYNAPI_PROC(SDL_bool,SDL_GamepadHasAxis,(SDL_Gamepad *a, SDL_GamepadAxis b),(a,b),return)
@@ -322,7 +322,7 @@ SDL_DYNAPI_PROC(SDL_Joystick*,SDL_GetJoystickFromPlayerIndex,(int a),(a),return)
 SDL_DYNAPI_PROC(SDL_JoystickGUID,SDL_GetJoystickGUID,(SDL_Joystick *a),(a),return)
 SDL_DYNAPI_PROC(SDL_JoystickGUID,SDL_GetJoystickGUIDFromString,(const char *a),(a),return)
 SDL_DYNAPI_PROC(void,SDL_GetJoystickGUIDInfo,(SDL_JoystickGUID a, Uint16 *b, Uint16 *c, Uint16 *d, Uint16 *e),(a,b,c,d,e),)
-SDL_DYNAPI_PROC(void,SDL_GetJoystickGUIDString,(SDL_JoystickGUID a, char *b, int c),(a,b,c),)
+SDL_DYNAPI_PROC(int,SDL_GetJoystickGUIDString,(SDL_JoystickGUID a, char *b, int c),(a,b,c),return)
 SDL_DYNAPI_PROC(Uint8,SDL_GetJoystickHat,(SDL_Joystick *a, int b),(a,b),return)
 SDL_DYNAPI_PROC(SDL_JoystickGUID,SDL_GetJoystickInstanceGUID,(SDL_JoystickID a),(a),return)
 SDL_DYNAPI_PROC(SDL_JoystickID,SDL_GetJoystickInstanceID,(SDL_Joystick *a),(a),return)
@@ -417,7 +417,7 @@ SDL_DYNAPI_PROC(SDL_SensorID*,SDL_GetSensors,(int *a),(a),return)
 SDL_DYNAPI_PROC(int,SDL_GetShapedWindowMode,(SDL_Window *a, SDL_WindowShapeMode *b),(a,b),return)
 SDL_DYNAPI_PROC(int,SDL_GetSurfaceAlphaMod,(SDL_Surface *a, Uint8 *b),(a,b),return)
 SDL_DYNAPI_PROC(int,SDL_GetSurfaceBlendMode,(SDL_Surface *a, SDL_BlendMode *b),(a,b),return)
-SDL_DYNAPI_PROC(void,SDL_GetSurfaceClipRect,(SDL_Surface *a, SDL_Rect *b),(a,b),)
+SDL_DYNAPI_PROC(int,SDL_GetSurfaceClipRect,(SDL_Surface *a, SDL_Rect *b),(a,b),return)
 SDL_DYNAPI_PROC(int,SDL_GetSurfaceColorKey,(SDL_Surface *a, Uint32 *b),(a,b),return)
 SDL_DYNAPI_PROC(int,SDL_GetSurfaceColorMod,(SDL_Surface *a, Uint8 *b, Uint8 *c, Uint8 *d),(a,b,c,d),return)
 SDL_DYNAPI_PROC(int,SDL_GetSystemRAM,(void),(),return)
@@ -434,7 +434,7 @@ SDL_DYNAPI_PROC(SDL_TouchID,SDL_GetTouchDevice,(int a),(a),return)
 SDL_DYNAPI_PROC(SDL_TouchDeviceType,SDL_GetTouchDeviceType,(SDL_TouchID a),(a),return)
 SDL_DYNAPI_PROC(SDL_Finger*,SDL_GetTouchFinger,(SDL_TouchID a, int b),(a,b),return)
 SDL_DYNAPI_PROC(const char*,SDL_GetTouchName,(int a),(a),return)
-SDL_DYNAPI_PROC(void,SDL_GetVersion,(SDL_version *a),(a),)
+SDL_DYNAPI_PROC(int,SDL_GetVersion,(SDL_version *a),(a),return)
 SDL_DYNAPI_PROC(const char*,SDL_GetVideoDriver,(int a),(a),return)
 SDL_DYNAPI_PROC(int,SDL_GetWindowBordersSize,(SDL_Window *a, int *b, int *c, int *d, int *e),(a,b,c,d,e),return)
 SDL_DYNAPI_PROC(void*,SDL_GetWindowData,(SDL_Window *a, const char *b),(a,b),return)
@@ -643,7 +643,7 @@ SDL_DYNAPI_PROC(void,SDL_SetEventEnabled,(Uint32 a, SDL_bool b),(a,b),)
 SDL_DYNAPI_PROC(void,SDL_SetEventFilter,(SDL_EventFilter a, void *b),(a,b),)
 SDL_DYNAPI_PROC(void,SDL_SetGamepadEventsEnabled,(SDL_bool a),(a),)
 SDL_DYNAPI_PROC(int,SDL_SetGamepadLED,(SDL_Gamepad *a, Uint8 b, Uint8 c, Uint8 d),(a,b,c,d),return)
-SDL_DYNAPI_PROC(void,SDL_SetGamepadPlayerIndex,(SDL_Gamepad *a, int b),(a,b),)
+SDL_DYNAPI_PROC(int,SDL_SetGamepadPlayerIndex,(SDL_Gamepad *a, int b),(a,b),return)
 SDL_DYNAPI_PROC(int,SDL_SetGamepadSensorEnabled,(SDL_Gamepad *a, SDL_SensorType b, SDL_bool c),(a,b,c),return)
 SDL_DYNAPI_PROC(SDL_bool,SDL_SetHint,(const char *a, const char *b),(a,b),return)
 SDL_DYNAPI_PROC(SDL_bool,SDL_SetHintWithPriority,(const char *a, const char *b, SDL_HintPriority c),(a,b,c),return)
diff --git a/src/joystick/SDL_gamepad.c b/src/joystick/SDL_gamepad.c
index 19065b4a7..e818a1a3e 100644
--- a/src/joystick/SDL_gamepad.c
+++ b/src/joystick/SDL_gamepad.c
@@ -2679,14 +2679,15 @@ int SDL_GetGamepadPlayerIndex(SDL_Gamepad *gamepad)
 /**
  *  Set the player index of an opened gamepad
  */
-void SDL_SetGamepadPlayerIndex(SDL_Gamepad *gamepad, int player_index)
+int SDL_SetGamepadPlayerIndex(SDL_Gamepad *gamepad, int player_index)
 {
     SDL_Joystick *joystick = SDL_GetGamepadJoystick(gamepad);
 
     if (joystick == NULL) {
-        return;
+        /* SDL_SetError() will have been called already by SDL_GetGamepadJoystick() */
+        return -1;
     }
-    SDL_SetJoystickPlayerIndex(joystick, player_index);
+    return SDL_SetJoystickPlayerIndex(joystick, player_index);
 }
 
 Uint16 SDL_GetGamepadVendor(SDL_Gamepad *gamepad)
diff --git a/src/joystick/SDL_joystick.c b/src/joystick/SDL_joystick.c
index de2526779..f5556a316 100644
--- a/src/joystick/SDL_joystick.c
+++ b/src/joystick/SDL_joystick.c
@@ -2826,9 +2826,9 @@ SDL_JoystickType SDL_GetJoystickType(SDL_Joystick *joystick)
 }
 
 /* convert the guid to a printable string */
-void SDL_GetJoystickGUIDString(SDL_JoystickGUID guid, char *pszGUID, int cbGUID)
+int SDL_GetJoystickGUIDString(SDL_JoystickGUID guid, char *pszGUID, int cbGUID)
 {
-    SDL_GUIDToString(guid, pszGUID, cbGUID);
+    return SDL_GUIDToString(guid, pszGUID, cbGUID);
 }
 
 /* convert the string version of a joystick guid to the struct */
diff --git a/src/video/SDL_surface.c b/src/video/SDL_surface.c
index 7f76595b9..7d1b587e4 100644
--- a/src/video/SDL_surface.c
+++ b/src/video/SDL_surface.c
@@ -615,11 +615,16 @@ SDL_SetSurfaceClipRect(SDL_Surface *surface, const SDL_Rect *rect)
     return SDL_GetRectIntersection(rect, &full_rect, &surface->clip_rect);
 }
 
-void SDL_GetSurfaceClipRect(SDL_Surface *surface, SDL_Rect *rect)
+int SDL_GetSurfaceClipRect(SDL_Surface *surface, SDL_Rect *rect)
 {
-    if (surface && rect) {
-        *rect = surface->clip_rect;
+    if (!surface) {
+        return SDL_InvalidParamError("surface");
     }
+    if (!rect) {
+        return SDL_InvalidParamError("rect");
+    }
+    *rect = surface->clip_rect;
+    return 0;
 }
 
 /*