diff --git a/script/install_PETSC.sh b/script/install_PETSC.sh
index 81bcbfc22a96d5d90e942887e2016b240b68dddc..34689ab03e659e67da1d6b66a8483ea81fb80d72 100755
--- a/script/install_PETSC.sh
+++ b/script/install_PETSC.sh
@@ -233,7 +233,7 @@ if [ ! -d "$1/SUPERLU_DIST" ]; then
   mkdir build
   cd build
 
-  cmake .. -DCMAKE_C_FLAGS="-fPIC" -DTPL_BLAS_LIBRARIES="$1/OPENBLAS/lib/libopenblas.a"  -DCMAKE_INSTALL_PREFIX="$1/SUPERLU_DIST"  -DCMAKE_EXE_LINKER_FLAGS="-L$1/METIS/lib -lmetis"  -DTPL_PARMETIS_INCLUDE_DIRS="$1/PARMETIS/include/;$1/METIS/include/" -DTPL_PARMETIS_LIBRARIES="$1/PARMETIS/lib/libparmetis.a"
+  cmake .. -DCMAKE_C_FLAGS="-fPIC" -DMPI_C_COMPILE_FLAGS="-std=c99"  -DTPL_BLAS_LIBRARIES="$1/OPENBLAS/lib/libopenblas.a"  -DCMAKE_INSTALL_PREFIX="$1/SUPERLU_DIST"  -DCMAKE_EXE_LINKER_FLAGS="-L$1/METIS/lib -lmetis"  -DTPL_PARMETIS_INCLUDE_DIRS="$1/PARMETIS/include/;$1/METIS/include/" -DTPL_PARMETIS_LIBRARIES="$1/PARMETIS/lib/libparmetis.a"
 
   # Installation for linux