How to force netcdf parallel build in Paraview 5.10.0

Development
1

Hi,
I’m trying to rebuild paraview 5.10.0 as a debian package for Debian/Testing
I would like to make a clean build using hdf5 mpi version.

This is why I have to rebuild netcdf requirement instead of using netcdf packages.
But it seems that necdf (from VTK Thirdparty) is not build with mpi support
vtk_netcdf_has_parallel is equal to FALSE which iduces errors when building vtkioss.

How can I force the netcdf to be build with mpi support?
Thanks for your help

Best

2

The embedded copies are generally as simple as they come. NetCDF needs to be provided from externally if it is to be MPI-aware. There is logic to forward MPI if the HDF5 is parallel, but that doesn’t make NetCDF itself parallel.

3

My point is that I run into an issue with vtkioss when either using netcdf debian package or vtknetcdf:

In file included from /build/paraview-5.10.0~rc2/VTK/Utilities/MPI/vtk_mpi.h:26,
                 from /build/paraview-5.10.0~rc2/build.python3.9/VTK/ThirdParty/hdf5/vtk_hdf5.h:26,
                 from /build/paraview-5.10.0~rc2/VTK/ThirdParty/ioss/vtkioss/cgns/Iocgns_Utils.C:58:
/usr/lib/x86_64-linux-gnu/openmpi/include/mpi.h:419:37: error: conflicting declaration 'typedef struct ompi_communicator_t* MPI_Comm'
  419 | typedef struct ompi_communicator_t *MPI_Comm;
      |                                     ^~~~~~~~
In file included from /build/paraview-5.10.0~rc2/VTK/ThirdParty/ioss/vtkioss/Ioss_GroupingEntity.h:12,
                 from /build/paraview-5.10.0~rc2/VTK/ThirdParty/ioss/vtkioss/Ioss_Assembly.h:14,
                 from /build/paraview-5.10.0~rc2/VTK/ThirdParty/ioss/vtkioss/cgns/Iocgns_Utils.C:7:
/build/paraview-5.10.0~rc2/VTK/ThirdParty/ioss/vtkioss/Ioss_CodeTypes.h:76:7: note: previous declaration as 'using MPI_Comm = int'
   76 | using MPI_Comm       = int;
      |       ^~~~~~~~

This problem arises from not having SEACAS_HAVE_MPI ON, right?
It seems that vtk_netcfd_has_parallel is required to have SEACAS_HAVE_MPI ON
That’s why I was trying to build vtknetcdf with mpi support

4

Yes, IOSS was set up that “I’m not using MPI, so no one must be using it”. This has been fixed upstream to instead use an Ioss_MPI_Comm name instead of squatting on the MPI_Comm name. It will be fixed in 5.10.1 (due in February).

5

Ok thanks.
Just a last question
If I want to explicitly disable ioss in paraview build I have to use
-DVTK_ENABLE_IOSS=OFF ?

6

I don’t see any record of that variable, so I don’t think that’d do anything.

You can pass VTK_MODULE_ENABLE_VTK_ioss=NO, but looking, I think this may end up conflicting with VTK::IOIOSS being required in “standard” ParaView builds. You may need to choose a different PARAVIEW_BUILD_EDITION setting.

Looking deeper, it looks like netcdf also has MPI_Comm conflicting decisions that need to be resolved…

7

Actually, IOSS hasn’t fixed it either. I confused it with a similar change. I’ll work on that upstream.

8

FindNetCDF.cmake (5.4 KB)

I’ve tried to use the above FindNetCDF.cmake alongside with libnetcdf-mpi-dev
It seems to compile smoothly provided you add tihs option to cmake:
-DCMAKE_PREFIX_PATH="/usr/lib/$(DEB_HOST_MULTIARCH)/cmake/netCDF_mpi"

with DEB_HOST_MULTIARCH=x86_64-linux-gnu in my case (Debian/Testing)