diff --git a/src/or/dirserv.c b/src/or/dirserv.c
index 92c789ec60..45de98265d 100644
--- a/src/or/dirserv.c
+++ b/src/or/dirserv.c
@@ -1565,7 +1565,7 @@ generate_v2_networkstatus(void)
         const char *eos = find_whitespace(ri->platform+4);
         char *platform = tor_strndup(ri->platform+4, eos-(ri->platform+4));
         if (tor_snprintf(outp, endp-outp,
-                         "opt v %s\n", platform)) {
+                         "opt v %s\n", platform)<0) {
           log_warn(LD_BUG, "Unable to print router version.");
           goto done;
         }