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From: "Dave Korn" <dave DOT korn AT artimi DOT com>
To: "'Andrew Makhorin'" <mao AT gnu DOT org>, "'Robin Walker'" <rdhw AT cam DOT ac DOT uk>
Cc: <cygwin AT cygwin DOT com>, "'Peter Rosin'" <peda AT lysator DOT liu DOT se>
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Subject: RE: strange bug in gettimeofday function
Date: Fri, 16 Feb 2007 15:24:26 -0000
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On 16 February 2007 13:36, Andrew Makhorin wrote:


> The irony is that I usually give the same standard explanation about
> floating-point to people who do not understand that :) *Unfortunately*,
> you are right, and the difference really appears because the second
> value returned by get_time being computed with full 80-bit precision
> is kept in a fpu register during the comparison while the first value
> is stored and then loaded as a 64-bit value. 


  This is the infamous http://gcc.gnu.org/PR323.  See in particular comment
#60 for a solution (although IIRC _FPU_SETCW doesn't exist on cygwin... maybe
I'll see about adding it).


    cheers,
      DaveK
-- 
Can't think of a witty .sigline today....


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