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Re: real.c implementation


> It failed completely for denormal numbers for which the target
> format also used a 15-bit exponent, i.e 80-bit double-extended
> and 128-bit quad precisions.
>
> we noticed two things, GCC
> did not always get denormals right

I have tried to investigate these statements as bug reports.  The
information provided is sketchy, but I think you may be referring to a
rounding feature that was left incomplete (and was so documented)
because it was never used.  The decimal-to-binary and binary-to-binary
conversions do know the intended output mode and do include the code
needed to round correctly.  On the other hand GCC's REAL_ARITHMETIC
macro should have a mode argument but does not, so the add, subtract,
multiply, divide programs default to the widest available result mode.
That created, in GCC, problems that are similar to the extra-precise
register mysteries of the Intel x86 floating point unit.

The program is used in other packages besides GCC, and its maintenance
will continue.  If you have a bug to report, please provide enough
information to reproduce the problem.


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