Re: [boost] MS VC10 std::numeric_limits<float>::max_digits10 is wrong for float

Subject: Re: [boost] MS VC10 std::numeric_limits<float>::max_digits10 is wrong for float
From: Paul A. Bristow (pbristow_at_[hidden])
Date: 2011-06-08 11:01:03

> -----Original Message-----
> From: boost-bounces_at_[hidden] [mailto:boost-bounces_at_[hidden]] On Behalf Of Stephan T.
> Lavavej
> Sent: Monday, June 06, 2011 7:03 PM
> To: boost_at_[hidden]
> Subject: Re: [boost] MS VC10 std::numeric_limits<float>::max_digits10 is wrong for float
> 
> [Paul A. Bristow]
> > https://connect.microsoft.com/VisualStudio/feedback/details/668921/
> > std-numeric-limits-float-max-digits10-value-of-8-is-wrong-and-should-be-9
> 
> > I trust this mistake will be corrected pronto  - but I'm not holding my breath :-(
> 
> This bug is currently assigned to me. I'll need to verify it, but it looks like you're right. I
can't promise
> anything, but I expect that we'll be able to fix it this month. However, the fix will be in VC11,
and NOT  released as a hotfix for VC10.

Assuming I am right, I think this means that we need yet another macro (Groans and Cries of Oh No,
not another!)

because

  BOOST_NO_NUMERIC_LIMITS_LOWEST

not defined is no longer an indicator that

   max_digits10 is available (and its values correct).

So do we need

  BOOST_NO_NUMERIC_LIMITS_MAX_DIGITS10

which should be defined by default, and only undefined for those libraries supporting C++0X
std::numeric_limits with correct values like recent GCC - and others (but not <= VC10)?

Views?

Paul

---
Paul A. Bristow,
Prizet Farmhouse, Kendal LA8 8AB  UK
[phone]  07714330204
pbristow_at_[hidden]