NaN traps

[Norman Diamond]

In article <14344 at bloom-beacon.MIT.EDU> tada at athena.mit.edu (Michael J Zehr) writes:

>I once wasted a lot of code dealing with something like:
>  if (data == 0) {zero_cnt++; continue;}
>  if NaN(data) {nan_cnt++; continue;}
>  do_something(data);
>if data was a bit pattern which was invalid, the
>comparison of it to 0 would change it's value to a particular number!!!

That seems like a somewhat illegal implementation.  I don't see an
"&" in front of data, and you didn't say you're using C++.  So the
NaN function can only get its hands on a COPY of data, and change
its COPY to a different value (according to K&R-*, ANSI, Version 6, etc.)

--
-- 
Norman Diamond, Sony Corporation (diamond at ws.sony.junet)
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