diff --git a/packages/muelu/src/Interface/MueLu_ParameterListInterpreter_def.hpp b/packages/muelu/src/Interface/MueLu_ParameterListInterpreter_def.hpp
index da3fec8fdcad..0fd850e5033b 100644
--- a/packages/muelu/src/Interface/MueLu_ParameterListInterpreter_def.hpp
+++ b/packages/muelu/src/Interface/MueLu_ParameterListInterpreter_def.hpp
@@ -1353,14 +1353,17 @@ namespace MueLu {
       TEUCHOS_TEST_FOR_EXCEPTION(partName != "zoltan" && partName != "zoltan2", Exceptions::InvalidArgument,
                                  "Invalid partitioner name: \"" << partName << "\". Valid options: \"zoltan\", \"zoltan2\"");
 
-      bool switched = false;
-      (void)switched;
 #ifndef HAVE_MUELU_ZOLTAN
+      bool switched = false;
       if (partName == "zoltan") {
         this->GetOStream(Warnings0) << "Zoltan interface is not available, trying to switch to Zoltan2" << std::endl;
         partName = "zoltan2";
         switched = true;
       }
+#else
+# ifndef HAVE_MUELU_ZOLTAN
+      bool switched = false;
+# endif
 #endif
 #ifndef HAVE_MUELU_ZOLTAN2
       if (partName == "zoltan2" && !switched) {
diff --git a/packages/muelu/test/scaling/DriverCore.hpp b/packages/muelu/test/scaling/DriverCore.hpp
index 112c5f61dac3..745b93b7a323 100644
--- a/packages/muelu/test/scaling/DriverCore.hpp
+++ b/packages/muelu/test/scaling/DriverCore.hpp
@@ -223,6 +223,40 @@ void PreconditionerSetup(Teuchos::RCP<Xpetra::Matrix<Scalar,LocalOrdinal,GlobalO
 }
 
 
+#if defined(HAVE_MUELU_EPETRA)
+
+// Helper functions for compilation purposes
+template<class Scalar, class LocalOrdinal, class GlobalOrdinal, class Node>
+struct Matvec_Wrapper{
+  static void UnwrapEpetra(Teuchos::RCP<Xpetra::Matrix<Scalar,LocalOrdinal,GlobalOrdinal,Node> >& A,
+                           Teuchos::RCP<Xpetra::MultiVector<Scalar,LocalOrdinal,GlobalOrdinal,Node> >& X,
+                           Teuchos::RCP<Xpetra::MultiVector<Scalar,LocalOrdinal,GlobalOrdinal,Node> >& B,
+                           Teuchos::RCP<const Epetra_CrsMatrix>& Aepetra,
+                           Teuchos::RCP<Epetra_MultiVector>& Xepetra,
+                           Teuchos::RCP<Epetra_MultiVector>& Bepetra) {
+    throw std::runtime_error("Template parameter mismatch");
+  }
+};
+
+
+template<class GlobalOrdinal>
+struct Matvec_Wrapper<double,int,GlobalOrdinal,Kokkos::Compat::KokkosSerialWrapperNode> {
+  static void UnwrapEpetra(Teuchos::RCP<Xpetra::Matrix<double,int,GlobalOrdinal,Kokkos::Compat::KokkosSerialWrapperNode> >& A,
+                           Teuchos::RCP<Xpetra::MultiVector<double,int,GlobalOrdinal,Kokkos::Compat::KokkosSerialWrapperNode> >& X,
+                           Teuchos::RCP<Xpetra::MultiVector<double,int,GlobalOrdinal,Kokkos::Compat::KokkosSerialWrapperNode> >& B,
+                           Teuchos::RCP<const Epetra_CrsMatrix>& Aepetra,
+                           Teuchos::RCP<Epetra_MultiVector>& Xepetra,
+                           Teuchos::RCP<Epetra_MultiVector>& Bepetra) {
+    typedef double SC;
+    typedef int LO;
+    typedef GlobalOrdinal GO;
+    typedef Kokkos::Compat::KokkosSerialWrapperNode NO;
+    Aepetra = Xpetra::Helpers<SC, LO, GO, NO>::Op2EpetraCrs(A);
+    Xepetra = Teuchos::rcp(& Xpetra::toEpetra(*X),false);
+    Bepetra = Teuchos::rcp(& Xpetra::toEpetra(*B),false);
+  }
+};
+#endif
 
 //*************************************************************************************
 template<class Scalar, class LocalOrdinal, class GlobalOrdinal, class Node>
@@ -271,13 +305,11 @@ void SystemSolve(Teuchos::RCP<Xpetra::Matrix<Scalar,LocalOrdinal,GlobalOrdinal,N
         Btpetra = rcp(& Xpetra::toTpetra(*B),false);
       }
 #endif
-#if defined(HAVE_MUELU_EPETRA) && !defined(HAVE_MUELU_INST_COMPLEX_INT_INT) && !defined(HAVE_MUELU_INST_FLOAT_INT_INT)
+#if defined(HAVE_MUELU_EPETRA)
       Teuchos::RCP<const Epetra_CrsMatrix> Aepetra;
       Teuchos::RCP<Epetra_MultiVector> Xepetra,Bepetra;
       if(lib==Xpetra::UseEpetra) {
-        Aepetra = Xpetra::Helpers<SC, LO, GO, NO>::Op2EpetraCrs(A);
-        Xepetra = rcp(& Xpetra::toEpetra(*X),false);
-        Bepetra = rcp(& Xpetra::toEpetra(*B),false);
+        Matvec_Wrapper<SC,LO,GO,NO>::UnwrapEpetra(A,X,B,Aepetra,Xepetra,Bepetra);
       }
 #endif
 
diff --git a/packages/xpetra/sup/Utils/Xpetra_MatrixUtils.hpp b/packages/xpetra/sup/Utils/Xpetra_MatrixUtils.hpp
index 922c36611d75..3df758169343 100644
--- a/packages/xpetra/sup/Utils/Xpetra_MatrixUtils.hpp
+++ b/packages/xpetra/sup/Utils/Xpetra_MatrixUtils.hpp
@@ -453,7 +453,7 @@ class MatrixUtils {
     Ac->getLocalDiagCopy(*diagVec);
 
     LocalOrdinal lZeroDiags = 0;
-    Teuchos::ArrayRCP< Scalar > diagVal = diagVec->getDataNonConst(0);
+    Teuchos::ArrayRCP< const Scalar > diagVal = diagVec->getData(0);
 
     for (size_t i = 0; i < rowMap->getNodeNumElements(); i++) {
       if (TST::magnitude(diagVal[i]) <= threshold) {
@@ -521,7 +521,7 @@ class MatrixUtils {
 #ifdef HAVE_XPETRA_DEBUG // only for debugging
     // check whether Ac has been repaired...
     Ac->getLocalDiagCopy(*diagVec);
-    Teuchos::ArrayRCP< Scalar > diagVal2 = diagVec->getDataNonConst(0);
+    diagVal = diagVec->getData(0);
     for (size_t r = 0; r < Ac->getRowMap()->getNodeNumElements(); r++) {
       if (TST::magnitude(diagVal[r]) <= threshold) {
         fos << "Error: there are too small entries left on diagonal after repair..." << std::endl;