diff --git a/dune/microstructure/CorrectorComputer.hh b/dune/microstructure/CorrectorComputer.hh
index ba76d79997c22e56454422c4275ad14580b940fd..01c18312b5a8236cbfae3e28c918bbebdb94265e 100644
--- a/dune/microstructure/CorrectorComputer.hh
+++ b/dune/microstructure/CorrectorComputer.hh
@@ -219,7 +219,7 @@ public:
       const auto& localFiniteElement = localView.tree().child(0).finiteElement();    // macht keinen Unterschied ob hier k oder 0..
       const auto nSf = localFiniteElement.localBasis().size();
       assert(arbitraryLeafIndex < nSf );
-      assert(arbitraryElementNumber  < basis_.gridView().size(0));   // "arbitraryElementNumber larger than total Number of Elements"
+      assert(arbitraryElementNumber  < (std::size_t)basis_.gridView().size(0));   // "arbitraryElementNumber larger than total Number of Elements"
 
       //Determine 3 global indices (one for each component of an arbitrary local FE-function)
       row = arbitraryComponentwiseIndices(arbitraryElementNumber,arbitraryLeafIndex);
@@ -660,7 +660,7 @@ public:
       localView.bind(element);
       // muLocal.bind(element);
       // lambdaLocal.bind(element);
-      const int localPhiOffset = localView.size();
+      const auto localPhiOffset = localView.size();
   //     Dune::Timer Time;
       //std::cout << "localPhiOffset : " << localPhiOffset << std::endl;
       ElementMatrixCT elementMatrix;
@@ -740,7 +740,7 @@ public:
       // lambdaLocal.bind(element);
       loadFunctional.bind(element);
 
-      const int localPhiOffset = localView.size();
+      const auto localPhiOffset = localView.size();
       //         std::cout << "localPhiOffset : " << localPhiOffset << std::endl;
 
       VectorCT elementRhs;
@@ -807,7 +807,7 @@ public:
     unsigned int arbitraryLeafIndex =  parameterSet_.template get<unsigned int>("arbitraryLeafIndex", 0);
     unsigned int arbitraryElementNumber =  parameterSet_.template get<unsigned int>("arbitraryElementNumber", 0);
     //Determine 3 global indices (one for each component of an arbitrary local FE-function)
-    Dune::FieldVector<int,3> row = arbitraryComponentwiseIndices(arbitraryElementNumber,arbitraryLeafIndex);
+    Dune::FieldVector<std::size_t,3> row = arbitraryComponentwiseIndices(arbitraryElementNumber,arbitraryLeafIndex);
 
     for (int k = 0; k<dim; k++)
     {
@@ -1426,7 +1426,7 @@ public:
     for (const auto& element : elements(basis_.gridView()))
     {
       localView.bind(element);
-      const int localPhiOffset = localView.size();
+      const auto localPhiOffset = localView.size();
 
       for(size_t i=0; i<localPhiOffset; i++)
       for(size_t j=0; j<localPhiOffset; j++ )