Re: Detecting NaN

[Stephen Leake <stephen.a.leake.1@gsfc.nasa.gov>]

"Marin David Condic" <dont.bother.mcondic.auntie.spam@acm.org> writes:

> Suppose I'm generating a Not A Number (NaN) in a floating point computation.
> If I'm using Gnat 3.13p, I'm pretty sure the way to get that detected is
> with the "-gnato" switch. (I have not tested it yet - someone else's code -
> but I'm pretty sure the problem is showing up because the code in question
> is not compiled with overflow checks on.) However, it might be advantageous
> to leave off the overflow checks and just force a check on the result. I
> seem to recall that there was an attribute or pragma or some other Ada
> language mechanism that would force a data item to be evaluated for
> correctness - say, after reading a record from a file. You might want to
> force an evaluationt that the language rules don't require until the record
> is actually accessed. I think that was the context in which I remember the
> mechanism being employed. Can anybody refresh my memory as to how that was
> done? Thanks.

'Valid.

> 
> 
> MDC -- Marin David Condic Senior Software Engineer Pace Micro
> Technology Americas www.pacemicro.com Enabling the digital
> revolution Web: http://www.mcondic.com/
> 
> 
> 

-- 
-- Stephe