When I do (eg): 
$d = unpack 'd',  pack 'h16', scalar reverse '7ff0000000000001'

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I expect $d to be set to the double represented by 7ff0000000000001, not to the double represented by 7ff8000000000001.

I, too, find that perl is assigning 7ff8000000000001 when it has been asked to assign 7ff0000000000001 and I regard this as a bug in perl - unless there's something in the pack/unpack documentation that allows for this unwanted behaviour.

I think a perlbug report should be filed for this.

Cheers,
Rob

In reply to Re: unintentional conversion of signaling NaN to quiet NaN by syphilis
in thread unintentional conversion of signaling NaN to quiet NaN by pryrt

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