On Sat, Feb 19, 2011 at 10:08 PM, Barry Smith <bsmith at mcs.anl.gov> wrote:
> > What about > > extern PetscErrorCode VecDestroy_(Vec); > #define VecDestroy(a) (VecDestroy_(a) || (((a) = 0),0)) > > Not exactly PETSc style, but allows the switch without changing the API. Why not let VecDestroy_() take the pointer? Also, what about having a configure mode that goes back to the old interface (on by default), but allow the new one to be configured. Might involve putting in #define stuff, or changing files a little, but it seems cleaner. Matt > > Barry > > On Feb 15, 2011, at 4:47 PM, Barry Smith wrote: > > > > > In MPI one calls MPI_Comm_free(&comm) to allow the MPI implementation to > set the pointer explicitly to 0 after the object is destroyed. > > > > In Petsc XXXDestroy() does not pass the pointer (because it seemed too > unnatural to me in 1994) thus not allowing 0ing the pointer. > > > > Was this a bad design decision? Should it be revisited? > > > > Barry > > > > Two use cases > > > > 1) error detection when someone tries to reuse a freed object > > > > 2) when removing some objects from a data structure that will be used > data one currently needs to do > > > > XXXXDestroy(mystruct->something);CHKERRQ(ierr); mystruct->something = 0; > > > > instead of the cleaner XXXDestroy(&mystruct->something);CHKERRQ(ierr); > > -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-dev/attachments/20110219/4a1f18d5/attachment.html>
