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Date: Wed, 19 Dec 2012 08:03:46 +0100
From: marco atzeri <marco DOT atzeri AT gmail DOT com>
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To: cygwin AT cygwin DOT com
Subject: Re: Bug in Cygwin strtod()
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On 12/19/2012 2:30 AM, KHMan wrote:
> On 12/19/2012 8:54 AM, Cary R. wrote:
>> The following code demonstrates a subtle bug in the Cygwin version of
>> strtod(). The value it generates is slightly different than the value
>> when using the math header files. This used to work correctly some
>> time ago (months). I just took the time to track the problem down in
>> our regression suite.
>>
>> #include<math.h>
>> #include<stdio.h>
>> #include<stdlib.h>
>>
>> int main()
>> {
>>      double value = M_LN10;
>>
>>      printf("generate const. - value: %0.15f.\n", value);
>>      printf("expected const. - value: 2.302585092994046.\n");
>>
>>      printf("\n");
>>      value = strtod("2.30258509299404568402", 0);
>>
>>      /* Note: the last digit is incorrect. */
>>      printf("generate strtod - value: %0.15f.\n", value);
>>      printf("expected strtod - value: 2.302585092994046.\n");
>>
>>      return 0;
>> }
>
> Yep, looks like the significand misses its mark by 1.
>

strtod is from newlib.
the last change in the code is one year and half ago

http://sourceware.org/cgi-bin/cvsweb.cgi/src/newlib/libc/stdlib/strtod.c.diff?r1=1.17&r2=1.18&cvsroot=src



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