+/* Support extended width event queues */
+#if EFSYS_OPT_EV_EXTENDED_WIDTH
+# if !EFSYS_OPT_RIVERHEAD
+# error "EV_EXTENDED_WIDTH requires RIVERHEAD"
+# endif
+#endif /* EFSYS_OPT_EV_EXTENDED_WIDTH */
+
+/* Support descriptor proxy queues */
+#if EFSYS_OPT_DESC_PROXY
+# if !EFSYS_OPT_RIVERHEAD
+# error "DESC_PROXY requires RIVERHEAD"
+# endif
+# if !EFSYS_OPT_EV_EXTENDED_WIDTH
+# error "DESC_PROXY requires EV_EXTENDED_WIDTH"
+# endif
+#endif /* EFSYS_OPT_DESC_PROXY */
+
+#if EFSYS_OPT_MAE
+# if !EFSYS_OPT_RIVERHEAD
+# error "MAE requires RIVERHEAD"
+# endif
+#endif /* EFSYS_OPT_MAE */
+
+#if EFSYS_OPT_VIRTIO
+# if !EFSYS_OPT_RIVERHEAD
+# error "VIRTIO requires RIVERHEAD"
+# endif
+# if !EFSYS_HAS_UINT64
+# error "VIRTIO requires UINT64"
+# endif
+#endif /* EFSYS_OPT_VIRTIO */
+