Cleaned up some compiler warnings.

src/cpuinfo/SDL_cpuinfo.c

@@ -458,10 +458,11 @@ SDL_GetCPUType(void)
 
     if (!SDL_CPUType[0]) {
         int i = 0;
-        int a, b, c, d;
 
         if (CPU_haveCPUID()) {
+            int a, b, c, d;
             cpuid(0x00000000, a, b, c, d);
+            (void) a;
             SDL_CPUType[i++] = (char)(b & 0xff); b >>= 8;
             SDL_CPUType[i++] = (char)(b & 0xff); b >>= 8;
             SDL_CPUType[i++] = (char)(b & 0xff); b >>= 8;
@@ -563,15 +564,12 @@ int
 SDL_GetCPUCacheLineSize(void)
 {
     const char *cpuType = SDL_GetCPUType();
-
+    int a, b, c, d;
+    (void) a; (void) b; (void) c; (void) d;
     if (SDL_strcmp(cpuType, "GenuineIntel") == 0) {
-        int a, b, c, d;
-
         cpuid(0x00000001, a, b, c, d);
         return (((b >> 8) & 0xff) * 8);
     } else if (SDL_strcmp(cpuType, "AuthenticAMD") == 0) {
-        int a, b, c, d;
-
         cpuid(0x80000005, a, b, c, d);
         return (c & 0xff);
     } else {

src/joystick/emscripten/SDL_sysjoystick.c

@@ -281,7 +281,7 @@ SDL_JoystickID SDL_SYS_GetInstanceIdOfDeviceIndex(int index)
     SDL_joylist_item *item = JoystickByIndex(index);
     if (item == NULL) {
         SDL_SetError("Joystick with index %d not found", index);
-        return NULL;
+        return 0;
     }
 
     return item->device_instance;

src/test/SDL_test_common.c

@@ -1204,10 +1204,10 @@ SDLTest_PrintEvent(SDL_Event * event)
                 event->tfinger.dx, event->tfinger.dy, event->tfinger.pressure);
         break;
     case SDL_DOLLARGESTURE:
-        SDL_Log("SDL_EVENT: Dollar gesture detect: %"SDL_PRIs64, event->dgesture.gestureId);
+        SDL_Log("SDL_EVENT: Dollar gesture detect: %"SDL_PRIs64, (long long) event->dgesture.gestureId);
         break;
     case SDL_DOLLARRECORD:
-        SDL_Log("SDL_EVENT: Dollar gesture record: %"SDL_PRIs64, event->dgesture.gestureId);
+        SDL_Log("SDL_EVENT: Dollar gesture record: %"SDL_PRIs64, (long long) event->dgesture.gestureId);
         break;
     case SDL_MULTIGESTURE:
         SDL_Log("SDL_EVENT: Multi gesture fingers: %d", event->mgesture.numFingers);

src/video/emscripten/SDL_emscriptenframebuffer.c

@@ -58,7 +58,6 @@ int Emscripten_CreateWindowFramebuffer(_THIS, SDL_Window * window, Uint32 * form
 
 int Emscripten_UpdateWindowFramebuffer(_THIS, SDL_Window * window, const SDL_Rect * rects, int numrects)
 {
-    static int frame_number;
     SDL_Surface *surface;
 
     SDL_WindowData *data = (SDL_WindowData *) window->driverdata;
@@ -115,6 +114,7 @@ int Emscripten_UpdateWindowFramebuffer(_THIS, SDL_Window * window, const SDL_Rec
     }, surface->w, surface->h, surface->pixels);
 
     /*if (SDL_getenv("SDL_VIDEO_Emscripten_SAVE_FRAMES")) {
+        static int frame_number = 0;
         char file[128];
         SDL_snprintf(file, sizeof(file), "SDL_window%d-%8.8d.bmp",
                      SDL_GetWindowID(window), ++frame_number);

src/video/emscripten/SDL_emscriptenvideo.c

@@ -227,7 +227,7 @@ Emscripten_CreateWindow(_THIS, SDL_Window * window)
                 return -1;
             }
         }
-        wdata->egl_surface = SDL_EGL_CreateSurface(_this, NULL);
+        wdata->egl_surface = SDL_EGL_CreateSurface(_this, 0);
 
         if (wdata->egl_surface == EGL_NO_SURFACE) {
             return SDL_SetError("Could not create GLES window surface");