Index: contrib/dma/dma.c
===================================================================
--- contrib/dma/dma.c
+++ contrib/dma/dma.c
@@ -459,6 +459,8 @@
 	bzero(&queue, sizeof(queue));
 	LIST_INIT(&queue.queue);
 
+	if (argc == 0)
+		errx(EX_OSERR, "invalid argc");
 	own_name = basename(argv[0]);
 
 	if (strcmp(own_name, "mailq") == 0) {