Re: [boost] [config] How does math_info report signalling NaNvalues?

From: AlisdairM (alisdair.meredith_at_[hidden])
Date: 2007-05-29 05:36:34

John Maddock wrote:

> Borland eh?

No comment ;?)
 
> Math_info relies on numeric_limits to return the correct answers to
> it's queries: with Borland it reports that it does have a quiet NaN,
> but as soon as you call numeric_limits<>::quiet_NaN() the program
> aborts with an unhandled hardware exception! :-(

The problem is not with quiet_NaN (a problem in the past) but with
signalling_NaN.  AFAICT, any attempt to evaluate this function should
signal, if the platform suports traps.  I don't understand how this
works on other platforms, so don't know what kind of workaround may be
necessary, other than commenting out that test entirely.

> Maybe we should add some #ifdef's in there so the program does at
> least run to completion?

I am experimenting with this now.

-- 
AlisdairM