diff --git a/src/tools/MergeVectorTools.h b/src/tools/MergeVectorTools.h
index 05e593f435..7cf18aef08 100644
--- a/src/tools/MergeVectorTools.h
+++ b/src/tools/MergeVectorTools.h
@@ -26,12 +26,7 @@
 #include <vector>
 #include <algorithm>
 #include <type_traits>
-#ifdef __NVCOMPILER
-#define PLMDAUTO typename C::value_type
-#else
-//I prefer letting gcc doing his work
-#define PLMDAUTO auto
-#endif
+
 namespace PLMD {
 
 namespace mergeVectorTools {
@@ -56,6 +51,12 @@ static void mergeSortedVectors(const C* const* vecs, std::size_t size, std::vect
     /// to allow using a priority_queu, which selects the highest element.
     /// we here (counterintuitively) define < as >
     bool operator< (Entry const& rhs) const { return top() > rhs.top(); }
+#ifdef __NVCOMPILER
+#define PLMDAUTO typename C::value_type
+#else
+//I prefer letting gcc doing his work
+#define PLMDAUTO auto
+#endif
     const PLMDAUTO & top() const { return *fwdIt; }
     void next() { ++fwdIt;};
   };