include: Fix casting on 64bit platforms.
diff --git a/src/include/cmocka.h b/src/include/cmocka.h
index 9720f04..0e8e25c 100755
--- a/src/include/cmocka.h
+++ b/src/include/cmocka.h
@@ -71,7 +71,7 @@
 
 /* Perform an unsigned cast to LargestIntegralType. */
 #define cast_to_largest_integral_type(value) \
-    ((LargestIntegralType)((unsigned)(size_t)(value)))
+    ((LargestIntegralType)((size_t)(value)))
 
 /* Smallest integral type capable of holding a pointer. */
 #ifndef _UINTPTR_T