[Cfp-interest 2038] Underflow

[Fred J. Tydeman]

N2746 is proposing for the definition of underflow:

[6] The result underflows if a nonzero result value with ordinary
accuracy would have magnitude (absolute value) no larger than the
minimum normalized number in the type.249

I would prefer:

[6] The result underflows if a nonzero result value, before rounding,
would have magnitude (absolute value) less than the minimum normalized
number in the type.249


Also, I believe that "inexact" should be added to the footnote as:

249)The term underflow here is intended to encompass both "gradual
underflow" as in IEC 60559 and also "flush-to-zero" underflow. IEC
60559 underflow can occur in cases where the magnitude of the inexact
rounded result equals the minimum normalized number in the format.


---
Fred J. Tydeman        Tydeman Consulting
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