[tex-live] strange discrepancy in running time of etex between TL2015 and TL2017

jfbu jfbu at free.fr
Sat Jul 29 09:45:45 CEST 2017

> http://www.bytereef.org/mpdecimal/
> but even then
> Power function:
> Results are not correctly rounded, even if the allcr context field is set to 1. This might change in a future release. The error of the function is less than 1ULP+t, where t has a maximum of 0.1ULP, but is almost always less than 0.01ULP.
> (power function with integer or half-integer exponent in xint currently achieves better precision than that, more like 0.5ULP + epsilon)

Hi, sorry for noise, but just to correct myself,
as the mpdecimal allows the various rounding modes
from the IBM specification, 


such as "round away from 0" it is normal that the error
is qualified as 1ULP+something. Probably when the rounding
mode is half_up, half_down, or half_even, then the library
achieves 0.5ULP + something, but the doc does not say so
in this quote,

I know I am drifting off topic, but I wanted
to correct my remark (people will read this 
in decades even centuries, so I have to tighten
the bolts)


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