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Re: clang support flagging

On Tue, 5 Jun 2012 14:03:55 +0200
Joerg Sonnenberger <> wrote:

> On Tue, Jun 05, 2012 at 12:58:09AM -0400, James K. Lowden wrote:
> > Bringing locales and 80-bit floating point to NetBSD seems to be a
> > matter of porting.  FreeBSD has both, and cephes has most of the C99
> > math.  
> The second part is not true. FreeBSD does not have complete long
> double support, they just cheat by aliasing most to the double
> version.

I'm not sure what "aliasing" you're referring to.  

The implementation for sqrtl() is here,

starting on line 75.  It might be slow, but afaict it does use 
80 bits.  It certainly works better than ours.  

> I also don't agree that long double support is that support,
> given the significant performance penalty on modern x86 cpus.

Performance is not a factor for compliance.  

Many C++ programs do not need long-double math, or don't use it in ways
that make performance critical.  A slow implementation can be later
optimized; non-implementation prevents use of the library.  


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