diff --git a/src/common/StateManager.hxx b/src/common/StateManager.hxx
index da4159b06..768c3385c 100644
--- a/src/common/StateManager.hxx
+++ b/src/common/StateManager.hxx
@@ -18,7 +18,7 @@
 #ifndef STATE_MANAGER_HXX
 #define STATE_MANAGER_HXX
 
-#define STATE_HEADER "06050300state"
+#define STATE_HEADER "06050301state"
 
 class OSystem;
 class RewindManager;
diff --git a/src/emucore/Thumbulator.hxx b/src/emucore/Thumbulator.hxx
index dcea53e5e..cf60670a0 100644
--- a/src/emucore/Thumbulator.hxx
+++ b/src/emucore/Thumbulator.hxx
@@ -311,7 +311,9 @@ class Thumbulator
     uInt32 _pipeIdx{0};
     CycleType _prefetchCycleType[3]{CycleType::S};
     CycleType _lastCycleType[3]{CycleType::S};
+#if 0 // unused for now
     AccessType _prefetchAccessType[3]{AccessType::data};
+#endif
    #ifdef EMULATE_PIPELINE
     uInt32 _fetchPipeline{0}; // reserve fetch cycles resulting from pipelining (execution stage)
     uInt32 _memory0Pipeline{0}, _memory1Pipeline{0};