diff --git a/server/request.h b/server/request.h
index eb710b9..604d115 100644
--- a/server/request.h
+++ b/server/request.h
@@ -1381,6 +1381,9 @@
 C_ASSERT( FIELD_OFFSET(struct send_hardware_message_request, y) == 52 );
 C_ASSERT( FIELD_OFFSET(struct send_hardware_message_request, time) == 56 );
 C_ASSERT( sizeof(struct send_hardware_message_request) == 64 );
+C_ASSERT( FIELD_OFFSET(struct send_hardware_message_reply, cursor) == 8 );
+C_ASSERT( FIELD_OFFSET(struct send_hardware_message_reply, count) == 12 );
+C_ASSERT( sizeof(struct send_hardware_message_reply) == 16 );
 C_ASSERT( FIELD_OFFSET(struct get_message_request, flags) == 12 );
 C_ASSERT( FIELD_OFFSET(struct get_message_request, get_win) == 16 );
 C_ASSERT( FIELD_OFFSET(struct get_message_request, get_first) == 20 );