diff --git a/arguments.c b/arguments.c
index 026272af..e2d18980 100644
--- a/arguments.c
+++ b/arguments.c
@@ -74,6 +74,7 @@ args_parse(const char *template, int argc, char **argv)
 
 	optreset = 1;
 	optind = 1;
+	optarg = NULL;
 
 	while ((opt = getopt(argc, argv, template)) != -1) {
 		if (opt < 0)
@@ -83,6 +84,7 @@ args_parse(const char *template, int argc, char **argv)
 			return (NULL);
 		}
 		args_set(args, opt, optarg);
+		optarg = NULL;
 	}
 	argc -= optind;
 	argv += optind;