Hi there, I found three source files: src/mpi/comm/comm_agree.c src/mpi/comm/comm_shrink.c src/glue/romio/all_romio_symbols.c where the MPIR functions were ending up in both the "mpi" and "pmpi" object files (we need to repackage the libraries in a slightly odd way on Mac, and this was causing that to fail). I fixed this by moving (or adding) the "#ifndef MPICH_MPI_FROM_PMPI" guards to ensure the MPIR symbols didn't end up in the "mpi" object files. This problem appears to still be present in the latest version 3.2 (I'm actually currently building 3.1.4). Best regards, Edric Ellis. _______________________________________________ discuss mailing list [email protected] To manage subscription options or unsubscribe: https://lists.mpich.org/mailman/listinfo/discuss