Re: Fw: Useless sNaNs... or useful?
On Oct 15 2010, Dan Zuras Intervals wrote:
>>
>> One important use is to initialize all floating point variables to
>> signaling NaNs. If they are inadvertently not properly initialized
What you & Ian probably don't know is that
I, along with Prof Kahan & Bob, advocated
for consistent behaviors for signalling NaNs
that would permit exactly this application.
Good. That would restore functionality that some compilers had
in 1970, though signalling NaNs is only one of many ways to achieve
the objective. It does, however, have the advantage that it has no
performance impact on code without such errors.
As it happened there were sound technical
reasons for features that made it infeasible.
All of which were thought to be more important
than this application. All of which I can
describe for you in detail but hesitate to do
so in this forum.
I am unaware of any, though I am aware of a great many UNSOUND technical
reasons :-(
Please could you describe the sound technical reasons? If you are
reluctant to do so in a semi-public forum, Email will do.
regards,
Nick Maclaren.