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Issue: FLOAT-UNDERFLOW (version 2)

Lucid 3.0 and later has LEAST-{NEGATIVE,POSITIVE}-NORMALIZED-<mumble>-FLOAT,
and in fact copied the names from Symbolics.  These, and the prescription 
that LEAST-{NEGATIVE,POSITIVE}-<mumble>-FLOAT be denormalized in 
implementatons which support it, seem very non-controversial to me.

But WITHOUT-FLOATING-UNDERFLOW-TRAPS is too limited.  The topic needs
more thought, because much more than "underflow" should be considered.
Lucid 3.0 and later has WITH-FLOATING-POINT-TRAPS, which takes two
lists of condition names relevant to floating point operations and
selectively enables or disables them (one list for "enablements", and
one for "disablements").  And I wouldn't like to bet on our being
able to achieve consensus on this design over the next few weeks,
even though I agree that it is an important topic.

-- JonL --