Re: [boost] Re: interval library: bug fix

From: Jens Maurer (Jens.Maurer_at_[hidden])
Date: 2004-01-17 08:41:51

Guillaume Melquiond wrote:
> The fix seems correct to me, but I'm not sure I like it. As Sylvain
> pointed it out to me, changing the return type is not the best thing to
> do. I benchmarked it with a small test (only subtractions) compiled with
> GCC (-O3 optimization). And it shows a huge performance drop when using
> interval<long double>: 70% slower!
> 
> So I'm obviously against forwarding this fix to the release branch.

The problem shows with any compiler where a "long double" is not
stored in memory completely, but as a double only.  This is possible
and legitimate.  A template indirection should be conditional on
"sizeof(long double) == 8" (use the workaround in this case).

Jens Maurer