Re: [boost] [serialization]Serialisation/deserialisationoffloating-point values

From: Paul A Bristow (pbristow_at_[hidden])
Date: 2006-05-03 16:43:52

|  -----Original Message-----
|  From: boost-bounces_at_[hidden] 
|  [mailto:boost-bounces_at_[hidden]] On Behalf Of Andras Erdei
|  Sent: 03 May 2006 21:24
|  To: boost_at_[hidden]
|  Subject: Re: 
|  [boost][serialization]Serialisation/deserialisationoffloating
|  -point values
|  
|  On 5/2/06, Paul A Bristow <pbristow_at_[hidden]> wrote:
|  >
|  > IMO The real issue here is not whether round-tripping 
|  should work, but that
|  > input from a long enough decimal digit string should 
|  always give you the nearest floating-point representation.
|  >
|  > For float this is true, and for double is almost (but not quite) true.
|  
|  [i've only read the abstract below, not the whole article, 
|  
|  William D. Clinger
|  How to read  floating point numbers accurately Proceedings 
|  of the ACM SIGPLAN 1990 conference on Programming language 
|  design and implementation

I've actually read the article!

 - though I must confess I didn't understand it all ;-(

However 'correct' input seems to be achieved by gcc,
and by MSVC for float, and almost for double.

So I stick to my guess that it is a bug.

It shouldn't be a feature IMO.

But I don't think there is anything that we should do (except be aware of
the potential problem).

It is up to Microsoft and/or Dinkumware to do nothing or resolve.

Paul

---
Paul A Bristow
Prizet Farmhouse, Kendal, Cumbria UK LA8 8AB
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