From: Jeff Squyres Date: January 18, 2008 1:13:33 PM CST To: mpi-21@XXXXXXXXXXXXX Cc: "mpi-21@cs.uiuc.edu" Subject: [mpi-21] const C++ MPI handles (take 2) Reply-To: mpi-21@XXXXXXXXXXXXX On Jan 18, 2008, at 2:02 PM, Erez Haba wrote: > Okay; about one issue at a time. Changing mail subject to reflect the discussion... > *For this sentence* it does not matter what's a common usage for C+ > + global variables. Some MPI implementations would need to have non- > const qualified global objects. Why? As I understand it, most (all?) MPI C++ implementations currently only require some objects to be non-const because of the standard-related issue that was already raised (Set_attr(), Set_name (), Set_errhandler() methods not having const variants). Is there a reason that an implementation would *need* MPI handles to be non-const? Per my prior mail, I believe that the standard should specify that some of the methods on these classes should have const and non-const variants, and then it should be fine to require that the predefined handles be const. So the question is still open: what's common practice in the C++ community regarding const/non-const global variable specification? This question will be moot if you can demonstrate that an implementation would need non-const C++ MPI predefined handles. -- Jeff Squyres Cisco Systems