On Wed, Feb 6, 2013 at 9:33 PM, Jed Brown <jedbrown at mcs.anl.gov> wrote:
> On Wed, Feb 6, 2013 at 7:35 PM, Barry Smith <bsmith at mcs.anl.gov> wrote: > >> >> In 1994 NULL was a pain because for different systems it was in >> different include files and sometimes you had to do very nasty stuff like >> >> #if !defined(NULL) >> #define NULL 0 >> >> This is why PETSC_NULL came into existence. >> >> Is the world a different place now? Based on the fact there are numerous >> (272 to be exact thanks to Karl) uses of NULL in PETSc today and they seem >> to cause absolutely no grief? (Except to Barry's tidy little mind) it seems >> PETSC_NULL is not needed any longer? >> >> If this is the case I propose we eradicate PETSC_NULL replacing it >> everywhere with NULL. >> > > We had a similar discussion a while back. > > http://lists.mcs.anl.gov/pipermail/petsc-dev/2011-November/006315.html > > Using NULL instead of PETSC_NULL does not help to safely pass a null > pointer value to a variadic function, but PETSC_NULL is also unsafe. > > Note that nearly all instances of 'NULL' are in either sieve (disabled by > default), examples, or pretty new code. (It's even possible that there were > zero occurrences in critical library back when we had that thread.) > However, there are certainly a few instances now and we've received no > mail, so I'm also in favor of replacing PETSC_NULL with NULL. > > It's C89 after all, so as long as we are sure to include stddef.h, we > should be fine. > I don't mind removing it, although the Fortran people still have to use something else. Matt -- 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/20130206/fb26def3/attachment.html>
