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Subject: [Bug libfortran/47945] REAL(8) output conversion error on MinGW32
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47945

--- Comment #4 from Thomas Henlich <thenlich at users dot sourceforge.net> 2011-03-01 14:44:54 UTC ---
(In reply to comment #3)
> 0.14285714285714284921875000000000 is still within the accuracy of IEEE double.
>  All numbers map to the same IEEE double.

This is technically correct; however a program should also observe portability
and usability rules and not just pick any number from a valid range, but the
number which is the most useful to the program user: either the one most common
across platforms and other compilers (0.14285714285714284921269268124888) or
the "shortest" one (0.14285714285714285000000000000000).

It is very hard to compare long numeric result listings obtained on different
platforms/compilers if some digits (however insignificant) never match.