Function mpi::ffi::PMPI_Graph_create

pub unsafe extern fn PMPI_Graph_create(comm_old: MPI_Comm,
                                       nnodes: c_int,
                                       index: *const c_int,
                                       edges: *const c_int,
                                       reorder: c_int,
                                       comm_graph: *mut MPI_Comm)
                                       -> c_int