Index: in6.h
===================================================================
RCS file: /cvsroot/src/sys/netinet6/in6.h,v
retrieving revision 1.96
diff -u -r1.96 in6.h
--- in6.h	5 Sep 2019 20:17:27 -0000	1.96
+++ in6.h	20 Sep 2019 00:53:02 -0000
@@ -126,7 +126,11 @@
 		__uint16_t  __u6_addr16[8];
 		uint32_t  __u6_addr32[4];
 	} __u6_addr;			/* 128-bit IP6 address */
-};
+}
+#ifdef _KERNEL
+__packed
+#endif
+;
 
 #define s6_addr   __u6_addr.__u6_addr8
 #ifdef _KERNEL	/* XXX nonstandard */