diff --git a/include/villas/nodes/test_rtt.hpp b/include/villas/nodes/test_rtt.hpp
index c6eecf26c..918ebbd1c 100644
--- a/include/villas/nodes/test_rtt.hpp
+++ b/include/villas/nodes/test_rtt.hpp
@@ -37,7 +37,7 @@ protected:
 
   public:
     Case(TestRTT *n, int id, int rate, int values, int limit,
-         std::string filename)
+         const std::string & filename)
         : node(n), id(id), rate(rate), values(values), limit(limit),
           filename(filename){};
 
@@ -65,7 +65,7 @@ protected:
 
 public:
   TestRTT(const uuid_t &id = {}, const std::string &name = "")
-      : Node(id, name), task(CLOCK_MONOTONIC), formatter(nullptr) {}
+      : Node(id, name), task(CLOCK_MONOTONIC), formatter(nullptr), stream(nullptr), cooldown(0), counter(-1) {}
 
   virtual ~TestRTT(){};
 
diff --git a/lib/nodes/test_rtt.cpp b/lib/nodes/test_rtt.cpp
index 2fdaab4a9..9a3fae63e 100644
--- a/lib/nodes/test_rtt.cpp
+++ b/lib/nodes/test_rtt.cpp
@@ -287,7 +287,7 @@ int TestRTT::_read(struct Sample *smps[], unsigned cnt) {
       task.setTimeout(cooldown);
     }
 
-    current_case++;
+    ++current_case;
 
     return 0;
   }