diff --git a/src/auth.c b/src/auth.c
index 66bc0f8a..3b3fa6e3 100644
--- a/src/auth.c
+++ b/src/auth.c
@@ -663,7 +663,7 @@ int auth_add_listener (const char *mount, client_t *client)
                 }
             }
             if (range)
-                INFO2 ("client %ld has unexpected range (%s), ignoring", CONN_ID (client), range);
+                INFO2 ("client %" PRI_ConnID " has unexpected range (%s), ignoring", CONN_ID (client), range);
         }
     }
     if (client->parser->req_type == httpp_req_head)
diff --git a/src/client.c b/src/client.c
index 84a568ce..7e2f04cf 100644
--- a/src/client.c
+++ b/src/client.c
@@ -153,7 +153,7 @@ void client_destroy(client_t *client)
         client->counter = client->schedule_ms = timing_get_time();
     } while (connection_reset (&client->connection, client->schedule_ms) < 0);  // loop back on failure to kick out
 
-    DEBUG2 ("keepalive detected on %s (%ld), placing back onto worker", CONN_ADDR(client), CONN_ID(client));
+    DEBUG2 ("keepalive detected on %s (%" PRI_ConnID "), placing back onto worker", CONN_ADDR(client), CONN_ID(client));
 
     client->flags = 0;
     client->ops = &http_request_ops;
diff --git a/src/format.c b/src/format.c
index 52412423..4bd1ce6c 100644
--- a/src/format.c
+++ b/src/format.c
@@ -454,7 +454,7 @@ static int apply_client_tweaks (ice_http_t *http, format_plugin_t *plugin, clien
             ice_http_printf (http, "Content-Range", 0, "bytes %" PRIu64 "-%" PRIu64 "/%s",
                     (uint64_t)client->connection.start_pos, last, total_size );
             http->in_length = range > 0 ? range : -1;
-            DEBUG3 ("client %ld, req %s range %ld requested\n", CONN_ID(client), client->mount, range);
+            DEBUG3 ("client %" PRI_ConnID ", req %s range %" PRIu64 " requested\n", CONN_ID(client), client->mount, range);
             if (range <= 100 && client->parser->req_type != httpp_req_head)
             {
                 char line [range+1];