diff --git a/include/sys/sa_impl.h b/include/sys/sa_impl.h
index 744c8dcb7d..fab7cd9e7e 100644
--- a/include/sys/sa_impl.h
+++ b/include/sys/sa_impl.h
@@ -177,7 +177,7 @@ typedef struct sa_hdr_phys {
 	 *
 	 */
 	uint16_t sa_layout_info;
-	uint16_t sa_lengths[1];	/* optional sizes for variable length attrs */
+	uint16_t sa_lengths[];	/* optional sizes for variable length attrs */
 	/* ... Data follows the lengths.  */
 } sa_hdr_phys_t;