Bug#182574: libc6: The pow() function gives incorrect results on special cases (nan, inf...)

[Vincent Lefevre <vincent@vinc17.org>]

On Thu, Feb 27, 2003 at 12:51:10 +0100, Vincent Lefevre wrote:
> On Thu, Feb 27, 2003 at 19:59:12 +0900, GOTO Masanori wrote:
> > Also look at Appendix F.9.4.4. instead of 7.12.7.4-2.
> 
> OK, I didn't know that they were normalized. I had a quick look at
> 
>   http://www.validlab.com/754R/standards/754.ps
> 
> (link from <http://www.validlab.com/754R/>), but I didn't see anything
> concerning transcendental functions. Perhaps an addition of IEC 60559
> over IEEE 754?

I've just seen:

       F.9  Mathematics <math.h>

       [#1] This  subclause  contains  specifications  of  <math.h>
       facilities  that  are  particularly  suited  for  IEC  60559
       implementations.
[...]
       [#3] Special cases for functions  in  <math.h>  are  covered
       directly or indirectly by IEC 60559.  The functions that IEC
       60559 specifies directly are identified in F.3.   The  other
       functions  in <math.h> treat infinities, NaNs, signed zeros,
       subnormals, and  (provided  the  state  of  the  FENV_ACCESS
       pragma  is  on)  the  exception flags in a manner consistent
       with the basic arithmetic operations covered by IEC 60559.

So, this seems to be an addition of the ISO C standard.

-- 
Vincent Lefèvre <vincent@vinc17.org> - Web: <http://www.vinc17.org/> - 100%
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