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Re: TR1 Math Special Functions
On Thu, 8 Feb 2007, Ian Lance Taylor wrote:
| Paolo Carlini <pcarlini@suse.de> writes:
|
| > > Or is there a __builtin_isnan to use?
| > >
| > Maybe that will just work! ;) I just tried and in mainline apparently
| > we are able to fully expand it without library calls. I would ask Ed
| > to try simply use the builtin and regtest on as many targets he
| > can. It would be nice if a compiler guy could confirm that such
| > library calls are never issued for __builtin_isnan irrespective of the
| > target. I'm CC-ing Ian... Apparently the documentation is a little
| > weak about such builtins..
|
| __builtin_isnan will always be fully expanded. It may generate a
| library call to, e.g., __nedf2, but it will never generate a call to
| isnan.
Sweet!
-- Gaby