diff --git a/dune/solvers/test/cgsteptest.cc b/dune/solvers/test/cgsteptest.cc
index 3bf9ac762811bde627254272f8f1a8dbf1015b44..d78da6d22fe0120d9de3fe61af17c4154699a18e 100644
--- a/dune/solvers/test/cgsteptest.cc
+++ b/dune/solvers/test/cgsteptest.cc
@@ -172,7 +172,7 @@ struct CGTestSuite
 
 int main(int argc, char** argv) try
 {
-    Dune::MPIHelper& helper = Dune::MPIHelper::instance(argc, argv);
+    Dune::MPIHelper::instance(argc, argv);
     bool passed(true);
 
     CGTestSuite testsuite;
diff --git a/dune/solvers/test/genericvectortoolstest.cc b/dune/solvers/test/genericvectortoolstest.cc
index 22dad8092ec9af2b84513140c7753bbd472a563f..bba5a0d8a5b8d03659dc1d093cc8505947cdff28 100644
--- a/dune/solvers/test/genericvectortoolstest.cc
+++ b/dune/solvers/test/genericvectortoolstest.cc
@@ -55,7 +55,7 @@ bool check()
 
 int main(int argc, char** argv) try
 {
-    Dune::MPIHelper& helper = Dune::MPIHelper::instance(argc, argv);
+    Dune::MPIHelper::instance(argc, argv);
     bool passed(true);
 
     static const size_t vec_size = 7;
diff --git a/dune/solvers/test/lowrankoperatortest.cc b/dune/solvers/test/lowrankoperatortest.cc
index 12c514c5f704f322f5654b50885264924fbedefc..7b869a508f259ce2aece2edd730045c8f082d77e 100644
--- a/dune/solvers/test/lowrankoperatortest.cc
+++ b/dune/solvers/test/lowrankoperatortest.cc
@@ -184,7 +184,7 @@ int main(int argc, char** argv) try
 {
 //    static const int block_size = BLOCKSIZE;
 
-    Dune::MPIHelper& helper = Dune::MPIHelper::instance(argc, argv);
+    Dune::MPIHelper::instance(argc, argv);
     bool passed(true);
 
     passed = check<Dune::Matrix<Dune::ScaledIdentityMatrix<double, 1> > >();
diff --git a/dune/solvers/test/mmgtest.cc b/dune/solvers/test/mmgtest.cc
index 27a1c0990887396ebc4e31589a44c0326265d2db..d63e89c0276880f9fc05537c16525ebd7aa1f39f 100644
--- a/dune/solvers/test/mmgtest.cc
+++ b/dune/solvers/test/mmgtest.cc
@@ -176,7 +176,7 @@ bool checkWithYaspGrid(int refine, const std::string fileName="")
 
 int main(int argc, char** argv) try
 {
-    Dune::MPIHelper& helper = Dune::MPIHelper::instance(argc, argv);
+    Dune::MPIHelper::instance(argc, argv);
     bool passed(true);
 
 
diff --git a/dune/solvers/test/multigridtest.cc b/dune/solvers/test/multigridtest.cc
index 67104b1ea294d102415be9e750bf75d4ca19b98c..9ab2acd6f21640cfe86b5ef2f7486f91eeedc484 100644
--- a/dune/solvers/test/multigridtest.cc
+++ b/dune/solvers/test/multigridtest.cc
@@ -176,7 +176,7 @@ struct MultigridTestSuite
 
 int main(int argc, char** argv) try
 {
-    Dune::MPIHelper& helper = Dune::MPIHelper::instance(argc, argv);
+    Dune::MPIHelper::instance(argc, argv);
     bool passed(true);
 
     MultigridTestSuite<1> testsuite1;
diff --git a/dune/solvers/test/nulloperatortest.cc b/dune/solvers/test/nulloperatortest.cc
index d8a1905633658887a53bd1b510cc46dc5609ccc8..aa8589c4a299fc143b7f8f860deeb03cb7b492e5 100644
--- a/dune/solvers/test/nulloperatortest.cc
+++ b/dune/solvers/test/nulloperatortest.cc
@@ -86,7 +86,7 @@ bool check()
 
 int main(int argc, char** argv) try
 {
-    Dune::MPIHelper& helper = Dune::MPIHelper::instance(argc, argv);
+    Dune::MPIHelper::instance(argc, argv);
 
     static const int block_size = BLOCKSIZE;
 
diff --git a/dune/solvers/test/obstacletnnmgtest.cc b/dune/solvers/test/obstacletnnmgtest.cc
index f1de17ef7160c0b413dc84dad1c8db81fa5c634b..4d68665a37a42c66b272ef4c8889b92d419083c5 100644
--- a/dune/solvers/test/obstacletnnmgtest.cc
+++ b/dune/solvers/test/obstacletnnmgtest.cc
@@ -176,7 +176,7 @@ bool checkWithYaspGrid(int refine, const std::string fileName="")
 
 int main(int argc, char** argv) try
 {
-    Dune::MPIHelper& helper = Dune::MPIHelper::instance(argc, argv);
+    Dune::MPIHelper::instance(argc, argv);
     bool passed(true);
 
 
diff --git a/dune/solvers/test/projectedgradienttest.cc b/dune/solvers/test/projectedgradienttest.cc
index 3a6796de15cb14a898a2bf2c928d8f8c662c71e6..8c551430ed9ce9d5aadf04acf355015fbab7dd89 100644
--- a/dune/solvers/test/projectedgradienttest.cc
+++ b/dune/solvers/test/projectedgradienttest.cc
@@ -143,7 +143,7 @@ bool checkWithYaspGrid(int refine, const std::string fileName, int maxIterations
 
 int main(int argc, char** argv) try
 {
-    Dune::MPIHelper& helper = Dune::MPIHelper::instance(argc, argv);
+    Dune::MPIHelper::instance(argc, argv);
     bool passed(true);
 
 
diff --git a/dune/solvers/test/quadraticipoptsolvertest.cc b/dune/solvers/test/quadraticipoptsolvertest.cc
index 7f3a945923725a1301f353167ae1661fe85433bb..1ec66100bcad2a2078969dafd7597bb98edbe383 100644
--- a/dune/solvers/test/quadraticipoptsolvertest.cc
+++ b/dune/solvers/test/quadraticipoptsolvertest.cc
@@ -154,7 +154,7 @@ bool checkWithYaspGrid(int refine, const std::string fileName="")
 
 int main(int argc, char** argv) try
 {
-    Dune::MPIHelper& helper = Dune::MPIHelper::instance(argc, argv);
+    Dune::MPIHelper::instance(argc, argv);
     bool passed(true);
 
 
diff --git a/dune/solvers/test/sumoperatortest.cc b/dune/solvers/test/sumoperatortest.cc
index 4e044f69d6631c038a7bd82ca83967bd29b0dacb..b08888767fa5f03d98c067cc4c0eddaec47d476b 100644
--- a/dune/solvers/test/sumoperatortest.cc
+++ b/dune/solvers/test/sumoperatortest.cc
@@ -172,7 +172,7 @@ bool check()
 
 int main(int argc, char** argv) try
 {
-    Dune::MPIHelper& helper = Dune::MPIHelper::instance(argc, argv);
+    Dune::MPIHelper::instance(argc, argv);
 
     static const int block_size = BLOCKSIZE;
 
diff --git a/dune/solvers/test/umfpacksolvertest.cc b/dune/solvers/test/umfpacksolvertest.cc
index 8fb0132810fc557453961395dfdf1879dc041889..79b145dfc386ac97db37d69d814767c365d4663e 100644
--- a/dune/solvers/test/umfpacksolvertest.cc
+++ b/dune/solvers/test/umfpacksolvertest.cc
@@ -103,7 +103,7 @@ struct UMFPackSolverTestSuite
 
 int main(int argc, char** argv) try
 {
-    Dune::MPIHelper& helper = Dune::MPIHelper::instance(argc, argv);
+    Dune::MPIHelper::instance(argc, argv);
 
     bool passed = true;