diff --git a/NumLib/DOF/LocalToGlobalIndexMap.cpp b/NumLib/DOF/LocalToGlobalIndexMap.cpp
index 696f9267a512dc682e9f6649745d1705c4eb83f0..4adb3786812c50cd0739f59bf4d601c2121c3306 100644
--- a/NumLib/DOF/LocalToGlobalIndexMap.cpp
+++ b/NumLib/DOF/LocalToGlobalIndexMap.cpp
@@ -310,7 +310,7 @@ LocalToGlobalIndexMap::getElementVariableIDs(std::size_t const mesh_item_id) con
     std::vector<std::size_t> vec;
     for (unsigned i=0; i<getNumberOfVariables(); i++)
     {
-        for (unsigned j=0; j<getNumberOfVariableComponents(i); j++)
+        for (int j=0; j<getNumberOfVariableComponents(i); j++)
         {
             auto comp_id = getGlobalComponent(i, j);
             if (!_rows(mesh_item_id, comp_id).empty())
diff --git a/NumLib/DOF/LocalToGlobalIndexMap.h b/NumLib/DOF/LocalToGlobalIndexMap.h
index c14202927978003b62e0a2207d509b1bb5063a04..7926a4c914abf9f178cc267e6868f2364c9836f3 100644
--- a/NumLib/DOF/LocalToGlobalIndexMap.h
+++ b/NumLib/DOF/LocalToGlobalIndexMap.h
@@ -105,7 +105,7 @@ public:
 
     std::size_t getNumberOfVariables() const { return (_variable_component_offsets.size() - 1); }
 
-    std::size_t getNumberOfVariableComponents(int variable_id) const
+    int getNumberOfVariableComponents(int variable_id) const
     {
         assert(static_cast<unsigned>(variable_id) < getNumberOfVariables());
         return _variable_component_offsets[variable_id+1] - _variable_component_offsets[variable_id];