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Re: Motion P1788/M0044:Constructors -- Voting Period begins - controlling rounding mode



On 2013-05-17 04:11:16 -0500, Ralph Baker Kearfott wrote:
> Yes, I am aware of access to changing the rounding mode in modern
> programming languages. What I was not aware of was that implementers
> interpreted this to apply to text-to-interval conversions, and that
> the text-to-interval conversion is done correctly from the point of
> view of interval computations.

Well, for string conversion, this is a bug. But all operations are
concerned by bugs, even the basic arithmetic operations. See:

  http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34678
  http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37838

For C's math.h functions, this is worse, as the ISO C standard doesn't
require the rounding direction to be honored. You could only rely on
QoI.

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Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/>
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