fix MPIFuture::get_mpidata

dune/common/parallel/mpifuture.hh

@@ -161,11 +161,11 @@ namespace Dune{
     }
 
     auto get_mpidata(){
-      return getMPIData<R>(*data_);
+      return getMPIData(*data_);
     }
 
     auto get_send_mpidata(){
-      return getMPIData<S>(*send_data_);
+      return getMPIData(*send_data_);
     }
   };
 

dune/common/parallel/test/mpifuturetest.cc

@@ -5,6 +5,15 @@
 #include <dune/common/parallel/mpihelper.hh>
 #include <dune/common/dynvector.hh>
 
+namespace Dune {
+  template<>
+  struct MPIData<const int&>{
+    // MPIData of reference type should not be used!
+    // This struct should never be used it just
+    // exists to generate a compiler error
+  };
+}
+
 int main(int argc, char** argv){
   auto& mpihelper = Dune::MPIHelper::instance(argc, argv);