[J3] function references and optimization

Toon Moene toon at moene.org
Thu Oct 11 16:59:51 EDT 2018

On 10/09/2018 10:15 PM, Bill Long via J3 wrote:

> Or a NaN.
> Like similar examples, I would expect the default behavior to enable optimizations that improve performance at the expense of strict IEEE rules. But there are usually compiler options to shut down optimizations, such as inlining or expression simplification.   If you have “well behaved” data, the optimized version is usually preferred. Real world simulations normally don’t involve infinities or NaNs. But if you want to double check, you can turn off the floating point optimizations and see if that affects the answer.

"Real world simulations normally don’t involve infinities or NaNs"

Exactly. That's why I invented the "optimization" option 
-ffinite-math-only for GCC (in 2002).


Apparently the community needed a Fortran guy to come up with this (see 
the followups).

Kind regards,

Toon Moene - e-mail: toon at moene.org - phone: +31 346 214290
Saturnushof 14, 3738 XG  Maartensdijk, The Netherlands
At home: http://moene.org/~toon/; weather: http://moene.org/~hirlam/
Progress of GNU Fortran: http://gcc.gnu.org/wiki/GFortran#news

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