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Re: [wayne@cs.toronto.edu: Cygwin-1.5.5 sscanf on floats: 20 timesslower than 2 years ago]


J. Johnston wrote:
Wayne Hayes wrote:

Since scanf and the floating point arithmetic is implemented in newlib,
I've redirected this message there.  Does anybody have an idea, what
could slow down float scanning in sscanf by a factor of 20?



Thanks! Just to be pedentic, I realized that it's worse than a factor of 20.
My *entire simulation* slows down by a factor of 20; there's significant
other computation in it. So the scanf slowdown is probably closer to
hundreds of times. *Something* fishy must be going on. :-)



The reason for the slow down is long double support. A new routine _strtold is used instead of _strtod_r. I am working on a patch to use the old routine for non-long-doubles to avoid the slow down.


-- Jeff J.


Patch checked in.


-- Jeff J.



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