1.7.8: Fortran I/O rounding inaccuracy

[Roger K. Wells]

On 03/07/2011 12:15 PM, Peter Brown wrote:
> Roger K. Wells<ROGER.K.WELLS<at>  saic.com>  writes:
>
>> On 03/07/2011 10:44 AM, Roger K. Wells wrote:
>>> On 03/07/2011 04:39 AM, Thomas Henlich wrote:
>>>> Hi,
>>>>
>>>> I found the following bug in cygwin 1.7.8 on Windows XP:
>>>>
>>>> Fortran I/O rounding truncates the result after a certain number of
>>>> digits. The following program:
>>>> ===
>>>> write(*, '(f35.32)') 0.14285714285714285d0
>>>> end
>>>> ===
>>>> gives this output:
>>>>    0.14285714285714284921269000000000
>>>> The expected output is:
>>>>    0.14285714285714284921269268124888
>>>>
> I don't think this has anything to do with cygin. On our linux system I get
>
> With Intel ifort:
>   0.14285714285714284921269268124888
>
> With gfortran 4.1.2s544
>   0.14285714285714284921269270000000
>
I agree.  It's a GCC problem.  I get the same results on Cygwin & Linux:
compiling with g77 gives correct output
compiling with gfortran does not.
rkw
>
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