CI: More tweaks to Hypre build options.

Author: kvrigor

.github/workflows/linux.yml

@@ -460,15 +460,22 @@ jobs:
           wget https://github.com/hypre-space/hypre/archive/v2.33.0.tar.gz
           tar xf v2.33.0.tar.gz && cd hypre-2.33.0
 
+          # Set Hypre backend
           if [[ "${{ matrix.config.backend }}" == "cuda" ]]; then
             BACKEND="CUDA"
           else
             BACKEND="OPENMP"
           fi
-          # Install
+
+          # Default Hypre build options are exposed below to know which Hypre features are enabled/disabled.
+          # See the full list of options here: https://hypre.readthedocs.io/en/latest/ch-misc.html#build-system-options
           cmake -S src -B bld                                \
                 -DCMAKE_C_COMPILER=mpicc                     \
+                -DCMAKE_CXX_COMPILER=mpicxx                  \
                 -DCMAKE_INSTALL_PREFIX="${PARFLOW_DEP_DIR}"  \
+                -DHYPRE_ENABLE_MPI="ON"                      \
+                -DHYPRE_ENABLE_HYPRE_LAPACK="OFF"            \
+                -DHYPRE_ENABLE_HYPRE_BLAS="OFF"              \
                 -DHYPRE_ENABLE_${BACKEND}="ON"
           cmake --build bld --parallel 4
           cmake --install bld