Battle of the FORTRAN Compilers...

[Doug Tody X217]

>From article <5799 at dftsrv.gsfc.nasa.gov>, by jim at jagubox.gsfc.nasa.gov (Jim Jagielski):
> 
> A long time ago I compared the NKR FORTRAN compiler with the AbSoft MacFORTRAN
> II compiler for A/UX. My original reviews tended to lean towards NKR since
> they had quicker compile times and very good support. NKR FORTRAN is now
> up to version 4.1 and some other changes have been made that make now a good
> time for a "new" review...
> 
> ...You can't really go wrong with either one. However, if you're using your
> FORTRAN to develop code, then MFII is the better choice, with it's support of
> sdb as it's extreme fine control over compiler options. Also, if you demand
> getting the most performance, MFII (with all optimizations set) will produce
> VERY quick code, though it will take a while to compile it :)

Another possibility is to use the Fortran-to-C translator F2C (available
from AT&T, research.att.com) in conjunction with a good C compiler such as
GCC.  This doesn't provide all the features of the Fortran compilers
mentioned above, is a bit slower, and is not quite as turn-key, but it is
*very* solid, and of course, it is free, you get the sources, and you can
redistribute.  I built a million line Fortran system using this combination
with only minor compiler problems with F2C/GCC, whereas the Absoft compiler
had serious optimizer problems with my code (it worked fine for some smaller
programs).  Examining the generated assembler for a simple DO-loop revealed
that F2C/GCC optimized the loop better than the Absoft compiler.  By way of
comparison, the SunOS Fortran compiler compiling for the same mc68020
architecture was much better than either in the case of the simple DO-loop
tested.  (The f77 compiler distributed with A/UX was hopeless.)

-- 
Doug Tody, National Optical Astronomy Observatories, Tucson AZ, 602-325-9217
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Internet: tody at noao.edu             SPAN/HEPNET: NOAO::TODY (NOAO=5355)