Re: open64 versus gcc

A.L. <alewando@fala2005.com> wrote:
[[about gcc]]
> One of the feature out of the list of "rich features" is that the
> results of numerical computations (such as inverting large matrix or
> solving large set of linear equations) strongly depends on activated
> options, especially optimization level.


This is just what you would expect for a computation which is
highly sensitive to small differences in roundoff errors.




> If you are a hobbyist, game programmer or GUI programmer, pretty
> likely gcc is good enough. If you do mission critical application,
> intensive number crunching or both, stay away from gcc.


I disagree. I've done heavy-duty number-crunching for a living for
over 20 years (simulating black hole collisions & similar problems).
I'm very happy with gcc, and would recommend it as an excellent compiler
for numerical work. It's not quite as good an optimizer as (say) the
Intel compiler, but it's usually within 10 or 20%. My colleagues and
I definitely find that the Intel compilers generate wrong code, or
abort with internal errors in valid code, considerably more often
than gcc. This is for both gcc 3.3* and gcc4, code usually a mix
of C, C++, Fortran 77, and Fortran 90.


ciao,


--
--
"Jonathan Thornburg -- remove -animal to reply" <jthorn@aei.mpg-zebra.de>
      Max-Planck-Institut fuer Gravitationsphysik (Albert-Einstein-Institut),
      Golm, Germany, "Old Europe" http://www.aei.mpg.de/~jthorn/home.html

Return to the comp.compilers page.
Search the comp.compilers archives again.