diff --git a/sdl.c b/sdl.c
--- a/sdl.c
+++ b/sdl.c
@@ -439,7 +439,7 @@ static uint32 ConvertSdlKeyIntoMy(SDL_ke
 	return (key << 16) + sym->unicode;
 }
 
-void DoExitSave(void);
+extern void DoExitSave(void);
 
 static int PollEvent(void)
 {