diff --git a/loader/src/myutils/overlay_helper.h b/loader/src/myutils/overlay_helper.h
index 3e7a35d..9911ede 100644
--- a/loader/src/myutils/overlay_helper.h
+++ b/loader/src/myutils/overlay_helper.h
@@ -9,7 +9,7 @@ extern "C" {
 
 struct buffer_store {
     void * buffer;
-    uint32_t buffer_size;
+    int32_t buffer_size;
     int32_t mode;
     int32_t surface_format;
     volatile int32_t buffering_mode;
diff --git a/src/overlay.c b/src/overlay.c
index 7104e54..66469ce 100644
--- a/src/overlay.c
+++ b/src/overlay.c
@@ -11,15 +11,15 @@
 #include <dirent.h>
 #include <wups.h>
 
-extern void (*OSScreenInit)(void);
-extern void (*OSScreenShutdown)(void);
-extern uint32_t (*OSScreenGetBufferSizeEx)(uint32_t bufferNum);
-extern int32_t (*OSScreenSetBufferEx)(uint32_t bufferNum, void * addr);
-extern int32_t (*OSScreenClearBufferEx)(uint32_t bufferNum, uint32_t temp);
-extern int32_t (*OSScreenFlipBuffersEx)(uint32_t bufferNum);
-extern int32_t (*OSScreenPutFontEx)(uint32_t bufferNum, uint32_t posX, uint32_t posY, const char * buffer);
-extern int32_t (*OSScreenEnableEx)(uint32_t bufferNum, int32_t enable);
-extern uint32_t (*OSScreenPutPixelEx)(uint32_t bufferNum, uint32_t posX, uint32_t posY, uint32_t color);
+void OSScreenInit(void);
+void OSScreenShutdown(void);
+uint32_t OSScreenGetBufferSizeEx(uint32_t bufferNum);
+void OSScreenSetBufferEx(uint32_t bufferNum, void * addr);
+void OSScreenClearBufferEx(uint32_t bufferNum, uint32_t temp);
+void OSScreenFlipBuffersEx(uint32_t bufferNum);
+void OSScreenPutFontEx(uint32_t bufferNum, uint32_t posX, uint32_t posY, const char * buffer);
+void OSScreenEnableEx(uint32_t bufferNum, int32_t enable);
+void OSScreenPutPixelEx(uint32_t bufferNum, uint32_t posX, uint32_t posY, uint32_t color);
 
 static void * overlayfunction_ptr __attribute__((section(".data"))) = NULL;