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RE: strange double comparison results with -O[12] on x86(-32)
- From: "Dave Korn" <dave dot korn at artimi dot com>
- To: "'Robert Dewar'" <dewar at adacore dot com>
- Cc: "'Florian Weimer'" <fw at deneb dot enyo dot de>,"'Andrew Pinski'" <pinskia at physics dot uc dot edu>,"'Christian Bodenstedt'" <c dot bodenstedt at cityweb dot de>,<gcc at gcc dot gnu dot org>
- Date: Tue, 14 Jun 2005 18:38:27 +0100
- Subject: RE: strange double comparison results with -O[12] on x86(-32)
----Original Message----
>From: Robert Dewar
>Sent: 14 June 2005 00:41
> Dave Korn wrote:
>
>> ... or it's a bug in the libc/crt-startup, which is where the hardware
>> rounding mode is (or should be) set up ...
>
> Well if you think that the operations should reflect IEEE 64-bit semantics
> (which is the only rationale for mucking with the rounding mode in the
> startup), then this is only an approximate fix, since the intermediate
> values still have excessive range, so you don't get infinities when
> expected.
As it happens, I wrote 'rounding mode' when I meant to say 'hardware
precision setting'.
Knowing my luck, I don't suppose this makes my statement any more correct,
but it may at least make it differently wrong! :)
cheers,
DaveK
--
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