dnsdist: Prevent a copy in DownstreamConnectionsManager::clear()

We don't care about performance in that place but it prevents a warning.

diff --git a/pdns/dnsdist-tcp.cc b/pdns/dnsdist-tcp.cc
index 0258585445737441e2f4b2329a0db67fe99fb70a..57ca6926dae5af28c7bff31cd74932317272ad6b 100644 (file)
--- a/pdns/dnsdist-tcp.cc
+++ b/pdns/dnsdist-tcp.cc
@@ -136,7 +136,7 @@ public:
   static size_t clear()
   {
     size_t count = 0;
-    for (const auto downstream : t_downstreamConnections) {
+    for (const auto& downstream : t_downstreamConnections) {
       count += downstream.second.size();
     }