On Jul 16, 2012, at 9:46 AM, Jed Brown wrote:

On Mon, Jul 16, 2012 at 9:44 AM, Shri <abhyshr@mcs.anl.gov> wrote:
  You need to do similar for your elemental grid to avoid memory leaks when using mpiuni.
http://petsc.cs.iit.edu/petsc/petsc-dev/rev/169c19e9ea54

Isn't the right solution to fix MPIUNI so that they aren't literally the same comm?

Yes, i think so too. If no one objects then i can do that. 
Btw, MPI_COMM_SELF and MPI_COMM_WORLD are same in mpiuni/mpi.h
#define MPI_COMM_WORLD       1
#define MPI_COMM_SELF        MPI_COMM_WORLD

 while the fortran version declares these communicators as different. mpiuni/mpif.h
 integer MPI_COMM_WORLD
       parameter (MPI_COMM_WORLD = 1)
       integer MPI_COMM_SELF
       parameter (MPI_COMM_SELF = 2)