introduce LONE_CHAR (optimized strcmp with one-char string)
diff --git a/networking/libiproute/ipaddress.c b/networking/libiproute/ipaddress.c
index 9fb08e6..e6130e4 100644
--- a/networking/libiproute/ipaddress.c
+++ b/networking/libiproute/ipaddress.c
@@ -678,7 +678,7 @@
 				if (brd_len) {
 					duparg("broadcast", *argv);
 				}
-				if (strcmp(*argv, "+") == 0) {
+				if (LONE_CHAR(*argv, '+')) {
 					brd_len = -1;
 				}
 				else if (LONE_DASH(*argv)) {