clang+libc++ using missing powl

[Steve Kargl]

On Fri, Sep 06, 2013 at 07:54:46AM +0100, David Chisnall wrote:
> 
> On 5 Sep 2013, at 22:09, Steve Kargl <sgk at troutmask.apl.washington.edu> wrote:
> 
> > On Thu, Sep 05, 2013 at 09:52:13AM +0100, David Chisnall wrote:
> >> On 4 Sep 2013, at 23:38, Baptiste Daroussin <bapt at freebsd.org> wrote:
> >> 
> >>> As a result we have a lot of fallouts of ports complaining about:
> >>> undefined reference to `powl'
> >>> 
> >>> It seems like libc++ is relying on a function we don't have yet
> >>> in libm, am I missing something?
> >> 
> >> I've attached a diff that I'd like to commit to msun
> > 
> > Why not disable libc++ from exposing these functions?
> 
> Because they're in the C++ spec and they should work.
> I consider this a placeholder until we have the real versions
> in the tree (the wiki says you have coshl, sinhl, and tanhl,
> in progress, any idea of an ETA for them)?  

Well, your commit has pre-empted any discussion on whether
there would have been a better kludge.  Oh well.

Concerning coshl, sinhl, and tanhl.  I had integrated bde's
code into msun and prepared a patch to commit over a week ago.
Unfortunately, my testing on sparc64 revealed a few issues
with tanhl, and Bruce and I are still discussing the fix.

PS: I have working erfl and erfcl for ld80 archs.  I'm still
testing and refining the code.  It turns out that computing
the needed rational approximation is fairly difficult (at least
for me).
 
-- 
Steve