CCL: Intel Fortran compiler

 Sent to CCL by: "Perry E. Metzger" []
 "David F. Green dfgreen,+,"
 <owner-chemistry/./> writes:
 > I should note, I'm generally a big fan of Free Software, and the Gnu
 > compilers are impressive in the range of achitectures they support,
 > but they simply do not produce particularly fast code, and sometimes
 > that needs to be considered (this applies to C/C++ as well as to
 > Fortran).
 That depends. For some architectures, languages, target programs, and
 versions of GCC, GCC works best. For others, it does not. It is very
 dependent, as I said, on the architecture you're running on, the
 language you're compiling, what code you're compiling, and (very very
 important!) which version of gcc and which optimization flags you set.
 I recommend benchmarking the code you're actually going to run on the
 machines you'll run it on -- nothing beats an actual experiment in
 cases like this. Especially if you're going to do a lot of
 computation, taking a little bit of time and trying a few things
 (including different settings of the optimization flags in your
 compilers) pays off handsomely in the end.
 Oh, and repeating that last bit one more time -- modern compilers have
 LOTS of optimizations you can turn on and off. Reading the
 documentation and experimenting with the flags is key. Never assume
 that the same optimizations will produce the best results for all
 programs you compile.