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Re: Reporting bugs: there is nothing to gain in frustrating reporters


On Sat, Jun 18, 2005 at 12:54:40PM +0200, Mattias Karlsson wrote:
> On Sat, 18 Jun 2005, Vincent Lefevre wrote:
> 
> >On 2005-06-16 17:54:03 -0400, Robert Dewar wrote:
> >>As you well know, not everyone agrees this is a bug, and this does
> >>not have to do with performance. Saying over and over again that you
> >>think it is a bug does not make it so.
> >
> >I haven't seen any correct argument why it could not be a bug.
> >Saying that the x86 processor is buggy is just completely silly.
> >Only some gcc developers think so.
> 
> Don't know about you, but I consider any processor that is unable to store 
> a register to memory and then read back the same value to be buggy.

That would indeed be a funny kind of processor, but x86 can store its
registers in memory exactly : simply store/reread them as long doubles.

> Sure, you can change rounding precision but according to my 2003 version 
> of "IA-32 Intel(r) Architecture Software Developer's Manual - Volume 
> 1: Basic Architecture"
>  a) That takes at least 4 instructions.
>  b) Only affects some instructions, and then only the result.
>  c) Only affects the significand and not the exponent.
> 
> Disclaimer: I haven't done any testing to verify that this is actually the 
> case since I have no access to x86 hardware.

-- 
Sylvain


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