Huw Davies (@huw) commented about programs/notepad/main.c:
dwStyle, 0, 0, rc.right, rc.bottom, hWnd, NULL, Globals.hInstance, NULL);
SetWindowSubclass(Globals.hEdit, (SUBCLASSPROC)&EDIT_CallBackProc, 0, 0);
You shouldn't need the ampersand in front of `EDIT_CallBackProc` - the identifier on its own refers to the function's address.