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From: "Dave Korn" <dave DOT korn AT artimi DOT com>
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Subject: RE: newlib?: pow function can produce incorrect results.
Date: Tue, 24 Apr 2007 03:23:43 +0100
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On 24 April 2007 03:14, Lev Bishop wrote:

> On 4/23/07, Dave Korn  wrote:
>> On 24 April 2007 00:53, Cary R. wrote:
>> 
>>> I had some more time to look into this and when the
>>> simple C program I mentioned earlier uses variables
>>> like the other program, incorrect results are
>>> produced. I have attached this C/C++ program. I
>>> certainly don't understand what is going on. I would
>>> have expected pow to be pass-by value which should
>>> make the two calls identical from a system standpoint,
>>> but the results imply something different. Any
>>> suggestions would be greatly appreciated.
>> 
>> 
>>   The notorious PR323.
> 
> Nah, in this case it's just that gcc's __builtin_pow() is more
> standards-compliant than newlib's pow().

  Yeh, after a second reading through the assembly I figure you're right.

  Maybe I should sleep every now and againzzzzzzzzzzzzzzzz......

    cheers,
      DaveK
-- 
Can't think of a witty .sigline today....


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