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Re: 80-bit subnormals printed incorrectly on Debian 11 M68K

On Jul 21 2021, Nelson H. F. Beebe wrote:

> The cause MIGHT be the incorrect value in <float.h> of LDBL_MIN_EXP:
> the M68K system has -16382, whereas test output from every other
> system in our farm that supports an 80-bit IEEE 754 format has -16381.

This is correct.  In the m68881 extended float format, denormals have an
exponent bias of 0x3fff, whereas in the i387 extended float format, the
bias is 0x3fffe.  That means that a normalized number in m68881 ext
format can have a biased exponent of zero.


Andreas Schwab, schwab@linux-m68k.org
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