MFC two minor fixes:

* Message when exiting with a deferred error code.
  * Don't crash on bad use of -W

usr.bin/tar/bsdtar.c

@@ -641,6 +641,9 @@ main(int argc, char **argv)
 	}
 
 	cleanup_exclusions(bsdtar);
+	if (bsdtar->return_value != 0)
+		bsdtar_warnc(bsdtar, 0,
+		    "Error exit delayed from previous errors.");
 	return (bsdtar->return_value);
 }
 
@@ -886,6 +889,10 @@ bsdtar_getopt(struct bsdtar *bsdtar, const char *optstring,
 				    "(matches both %s and %s)",
 				    p, (*poption)->name, option->name);
 
+			if ((*poption)->has_arg == required_argument
+			    && optarg == NULL)
+				bsdtar_errc(bsdtar, 1, 0,
+				    "Option \"%s\" requires argument", p);
 		} else {
 			opt = '?';
 			/* TODO: Set up a fake 'struct option' for