mpi_coll_reduce_scatter_fun = (int (*)(void *sbuf, void *rbuf, int *rcounts,MPI_Datatype dtype, MPI_Op op,
MPI_Comm comm)) mpi_coll_reduce_scatter_description[reduce_scatter_id].coll;
mpi_coll_reduce_scatter_fun = (int (*)(void *sbuf, void *rbuf, int *rcounts,MPI_Datatype dtype, MPI_Op op,
MPI_Comm comm)) mpi_coll_reduce_scatter_description[reduce_scatter_id].coll;