Package 'cdo': get rid of unnecessary dependency on MPI C++ library. (s…

…pack#6632)

var/spack/repos/builtin/packages/cdo/package.py

@@ -34,6 +34,8 @@ class Cdo(AutotoolsPackage):
     url = 'https://code.mpimet.mpg.de/attachments/download/12760/cdo-1.7.2.tar.gz'
     list_url = 'https://code.mpimet.mpg.de/projects/cdo/files'
 
+    maintainers = ['skosukhin']
+
     version('1.9.1', 'e60a89f268ba24cee5c461f2c217829e')
     version('1.9.0', '2d88561b3b4a880df0422a62e5027e40')
     version('1.8.2', '6a2e2f99b7c67ee9a512c40a8d4a7121')
@@ -133,8 +135,13 @@ def configure_args(self):
 
         config_args += self.enable_or_disable('openmp')
 
-        # Workaround for a problem in CDO
+        # Starting version 1.9.0 CDO is a C++ program but it uses the C
+        # interface of HDF5 without the parallel features. To avoid
+        # unnecessary dependencies on mpi's cxx library, we need to set the
+        # following flags. This works for OpenMPI, MPICH, MVAPICH, Intel MPI,
+        # IBM Spectrum MPI, bullx MPI, and Cray MPI.
         if self.spec.satisfies('@1.9:+hdf5^hdf5+mpi'):
-            config_args.append('CXX=' + self.spec['mpi'].mpicxx)
+            config_args.append(
+                'CPPFLAGS=-DOMPI_SKIP_MPICXX -DMPICH_SKIP_MPICXX')
 
         return config_args