This is the mail archive of the
mailing list for the Cygwin project.
Re: [email@example.com: Cygwin-1.5.5 sscanf on floats: 20 timesslower than 2 years ago]
- From: "J. Johnston" <jjohnstn at redhat dot com>
- To: Wayne Hayes <wayne at cs dot toronto dot edu>
- Cc: newlib at sources dot redhat dot com, cygwin at cygwin dot com
- Date: Fri, 21 Nov 2003 14:53:05 -0500
- Subject: Re: [firstname.lastname@example.org: Cygwin-1.5.5 sscanf on floats: 20 timesslower than 2 years ago]
- Organization: Red Hat Inc.
- References: <03Nov17.email@example.com>
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.
Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Problem reports: http://cygwin.com/problems.html