diff --git a/include/my_global.h b/include/my_global.h
index 86ef5f88..e9c94702 100644
--- a/include/my_global.h
+++ b/include/my_global.h
@@ -159,7 +159,7 @@
 #  if defined(__i386__) || defined(__ppc__)
 #    define SIZEOF_CHARP 4
 #    define SIZEOF_LONG 4
-#  elif defined(__x86_64__) || defined(__ppc64__)
+#  elif defined(__x86_64__) || defined(__ppc64__) || defined(__arm64__)
 #    define SIZEOF_CHARP 8
 #    define SIZEOF_LONG 8
 #  else
