[Cfp-interest 3102] Re: Issue: frexp and double-double underflow

[Fred J. Tydeman]

On Tue, 23 Apr 2024 22:56:50 -0600 (PDT) Fred J. Tydeman wrote:
>
>It is no different than frexp( DBL_TRUE_MIN*2.2, &exp);
>which returns DBL_TRUE_MIN*1.1 (which is not underflow)

Oops.  Wrong example.  That frexp() would return a value
between 0.5 and 1.0.

long double a = 1.L + DBL_TRUE_MIN;
long double b;

b = a / 2.L;  /* would return 0.5L + DBL_TRUE_MIN/2.L */

Which is not an underflow


---
Fred J. Tydeman        Tydeman Consulting
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