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[netCDF #QOI-309912]: netcdf4 MPI_Comm Problem with Open MPI

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  • Subject: [netCDF #QOI-309912]: netcdf4 MPI_Comm Problem with Open MPI
  • Date: Wed, 31 Mar 2010 07:44:04 -0600
> 
> Hi Ed,
> 
> it works with Open MPI, configure correctly sets HAVE_MPI_COMM_F2C to 1
> and I could run my program without any trouble.
> 
> But... I wonder if the code in libsrc4/nc4file.c works correctly with an MPI
> without MPI_Comm_f2c: nc_create_par is called with comm_c=0 and info_c=0.
> But it should pass the Fortran versions of the communicator and info object
> (as done in NetCDF 4.0.1):
> 
> int
> nc_create_par_fortran(const char *path, int cmode, int comm,
> int info, int *ncidp)
> {
> MPI_Comm comm_c = 0;
> MPI_Info info_c = 0;
> #ifdef USE_PARALLEL
> #ifdef HAVE_MPI_COMM_F2C
> comm_c = MPI_Comm_f2c(comm);
> info_c = MPI_Info_f2c(info);
> #else
> comm_c = (MPI_Comm)comm;
> info_c = (MPI_Info)info;
> #endif
> #endif
> return nc_create_par(path, cmode, comm_c, info_c, ncidp);
> }
> 
> 
> and the same changes for nc_open_par_fortran:
> 
> int
> nc_open_par_fortran(const char *path, int mode, int comm,
> int info, int *ncidp)
> {
> MPI_Comm comm_c = 0;
> MPI_Info info_c = 0;
> #ifdef USE_PARALLEL
> #ifdef HAVE_MPI_COMM_F2C
> comm_c = MPI_Comm_f2c(comm);
> info_c = MPI_Info_f2c(info);
> #else
> comm_c = (MPI_Comm)comm;
> info_c = (MPI_Info)info;
> #endif
> #endif
> return nc_open_par(path, mode, comm_c, info_c, ncidp);
> }
> 
> 
> 
> 
> matthias
> 

Howdy Matthias!

Thanks for pointing that out. Parallel test runs will happen tonight with the 
full nightly test build, and presumably that bug would have shown up then.

But I have fixed it as you suggest, and released a new snapshot if you want to 
take a look.

Thanks for all the help! NetCDF is a community-supported free software package, 
and we depend on the efforts of knowledgeable and helpful users like yourself!

Thanks,

Ed

Ticket Details
===================
Ticket ID: QOI-309912
Department: Support netCDF
Priority: Critical
Status: Closed