[petsc-dev] adding comm argument to PetscError() and friends

[Barry Smith]

   I'd like to add a MPI_Comm as the first argument to PetscError() and friends.

   In this way, if the same error is known over all the communicator ranks it 
can print just one nice error message and stack instead of spewing out many of 
the same messages all over the place.

   Does anyone object to this?

   It does mean for each SETERRQXXX() we call we need to select the correct 
comm that is passed in. I will do all that, worst case just use MPI_COMM_SELF 
for some and get the same effect as today.



   Barry