--- xnu/xnu-344.34/libkern/c++/OSNumber.cpp
+++ xnu/xnu-124.1/libkern/c++/OSNumber.cpp
@@ -21,23 +21,16 @@
  */
 /* IOOffset.m created by rsulack on Wed 17-Sep-1997 */
 
-#include <sys/cdefs.h>
-
-__BEGIN_DECLS
-extern int sscanf(const char *input, const char *fmt, ...);
-__END_DECLS
-
 #include <libkern/c++/OSNumber.h>
 #include <libkern/c++/OSString.h>
 #include <libkern/c++/OSSerialize.h>
 #include <libkern/c++/OSLib.h>
 
-#define sizeMask (~0ULL >> (64 - size))
+#define sizeMask ((1ULL << (size)) - 1)
 
 #define super OSObject
 
 OSDefineMetaClassAndStructors(OSNumber, OSObject)
-
 OSMetaClassDefineReservedUnused(OSNumber, 0);
 OSMetaClassDefineReservedUnused(OSNumber, 1);
 OSMetaClassDefineReservedUnused(OSNumber, 2);