diff --git a/dune/gfe/polardecomposition.hh b/dune/gfe/polardecomposition.hh
index 9f7098aeae2dfaa01cd30e81ad3887ca558ab7aa..3665392bd6df7c79f9f2c9b138618109fcddde27 100644
--- a/dune/gfe/polardecomposition.hh
+++ b/dune/gfe/polardecomposition.hh
@@ -244,7 +244,7 @@ namespace Dune::GFE {
                     mini = i;
 
             Pleft[3][mini]  = 1;
-            Pright[mini][3] = 1;      // Smalest element to the last position
+            Pright[mini][3] = 1;      // Smallest element to the last position
 
 
             for (int i = 0; i < 4; ++i) {
diff --git a/test/cosseratenergytest.cc b/test/cosseratenergytest.cc
index cdfc0f38c9d95afdf49e1aadd9cb380d69296214..9f4b5bc40e667f1355bf4531f6c25b5d889ecd44 100644
--- a/test/cosseratenergytest.cc
+++ b/test/cosseratenergytest.cc
@@ -7,8 +7,6 @@
 
 #include <dune/functions/functionspacebases/lagrangebasis.hh>
 
-#include <dune/fufem/functions/constantfunction.hh>
-
 #include <dune/gfe/rigidbodymotion.hh>
 #include <dune/gfe/cosseratenergystiffness.hh>
 
@@ -44,7 +42,7 @@ std::unique_ptr<GridType> makeSingleSimplexGrid()
         v[i] = i;
     factory.insertElement(GeometryTypes::simplex(domainDim), v);
 
-    return std::unique_ptr<GridType>(factory.createGrid());
+    return factory.createGrid();
 }
 
 
diff --git a/test/cosseratrodenergytest.cc b/test/cosseratrodenergytest.cc
index ff65271b6c6ed816cded185956c0158e4b1a1fd9..6a485ac5704538ca516071b8111c21702b149d0d 100644
--- a/test/cosseratrodenergytest.cc
+++ b/test/cosseratrodenergytest.cc
@@ -80,7 +80,7 @@ int main (int argc, char *argv[]) try
 
     std::vector<RigidBodyMotion<double,3> > referenceConfiguration(gridView.size(1));
 
-    for (const auto vertex : vertices(gridView))
+    for (const auto& vertex : vertices(gridView))
     {
         auto idx = gridView.indexSet().index(vertex);
 
diff --git a/test/polardecompositiontest.cc b/test/polardecompositiontest.cc
index cc10676d24424d59fc4316dace27efa2a9fb9720..779d929c07a21faa610704e10dab8f52b73abc02 100644
--- a/test/polardecompositiontest.cc
+++ b/test/polardecompositiontest.cc
@@ -168,7 +168,6 @@ static bool test4dDeterminant() {
 
 static bool testdominantEVNewton() {
     field_type detB = 0.992928;
-    field_type detM = 0.000620104;
     FieldVector<field_type,3>  minpol = {0, -1.99999, -0.00496083};
     double correctDominantEV = 1.05397;
 
diff --git a/test/surfacecosseratstressassemblertest.cc b/test/surfacecosseratstressassemblertest.cc
index 66cbddd561d31042533a57896b35b9730d5481e3..9e2ea9609c73b85646a9be8032e827ab63ab3754 100644
--- a/test/surfacecosseratstressassemblertest.cc
+++ b/test/surfacecosseratstressassemblertest.cc
@@ -92,7 +92,7 @@ static bool symmetryTest(std::unordered_map<std::string, FieldVector<double,d>>
 
 int main (int argc, char *argv[])
 {
-  MPIHelper& mpiHelper = MPIHelper::instance(argc, argv);
+  MPIHelper::instance(argc, argv);
 
   /////////////////////////////////////////////////////////////
   //                      CREATE THE GRID
@@ -186,7 +186,7 @@ int main (int argc, char *argv[])
   Functions::interpolate(basisOrderD, x, [](FieldVector<double,dim> x){ return x; });
   Functions::interpolate(basisOrderD, xInitial, [](FieldVector<double,dim> x){ return x; });
 
-  for (int i = 0; i < basisOrderD.size(); i++) {
+  for (std::size_t i = 0; i < basisOrderD.size(); i++) {
     std::stringstream stream;
     stream << x[i];
     //Look up the displacement for this vertex in the deformationMap
@@ -201,7 +201,7 @@ int main (int argc, char *argv[])
   DisplacementVector xOrderR;
   xOrderR.resize(basisOrderR.size());
   Functions::interpolate(basisOrderR, xOrderR, [](FieldVector<double,dim> x){ return x; });
-  for (int i = 0; i < basisOrderR.size(); i++) {
+  for (std::size_t i = 0; i < basisOrderR.size(); i++) {
     std::stringstream stream;
     stream << xOrderR[i];
     Rotation<double,dim> rotation(rotationMap.at(stream.str()));
diff --git a/test/targetspacetest.cc b/test/targetspacetest.cc
index d24e66514b7b95067cb314c864a3acd90f32718e..34b5a285dafc26c0411a2f02dc4bbd218584c331 100644
--- a/test/targetspacetest.cc
+++ b/test/targetspacetest.cc
@@ -374,7 +374,7 @@ int main() try
 
 } catch (Exception& e) {
 
-    std::cout << e << std::endl;
+    std::cout << e.what() << std::endl;
 
 }