diff --git a/build_io.sh b/build_io.sh
index 0b326ace059f53bd813c834ca7dccdc9cca683bb..45e3ee3897718301c28f28498477383d475a490e 100755
--- a/build_io.sh
+++ b/build_io.sh
@@ -25,9 +25,9 @@ elif [ "$2" == "gin" ]
 then
  module load gcc/4.8.2
  module load boost/1.54.0
- sh ./configure --with-boost=/sw/apps/boost/1.54.0/ --with-hdf5=$HOME/HDF5/bin/h5pcc
+ sh ./configure CXX=mpic++ --with-boost=/sw/apps/boost/1.54.0/ --with-hdf5=$HOME/HDF5/bin/h5pcc
 else
- sh ./configure --with-hdf5=$HOME/HDF5/bin/h5pcc
+ sh ./configure CXX=mpic++ --with-hdf5=$HOME/HDF5/bin/h5pcc
 fi
 make