NetBSD 6.1.5 doesn't have ldexpl in math.h

[Matthew Selsky]

On Thu, Sep 07, 2017 at 12:47:42PM -0700, Gary E. Miller via devel wrote:
> Yo Hal!
> 
> On Thu, 07 Sep 2017 01:37:30 -0700
> Hal Murray <hmurray at megapathdsl.net> wrote:
> 
> > > Got a workaround?   
> > 
> > This seems to build and check:
> > #include <math.h>       /* ldexpl() */
> > #ifndef ldexpl
> >   /* Missing in NetBSD 6.1.5 */
> >   #define ldexpl ldexp
> > #endif
> > 
> > Will that do the right conversions between double and long double?
> 
> Serious loss of precision, but maybe the best we can do.
> 
> > Do we want to work with old but still supported NetBSD or be sticky
> > about requiring C99?
> 
> You brougth it up.  If yuo don't care we can drop that version of NetBSD.

ldexpl() was added in NetBSD 7 (released Sept 2015).  NetBSD 6 was released in
Oct 2012 and last had a point release in Sept 2014).  NetBSD 6 is still
supported by upstream per https://www.netbsd.org/releases/formal.html#history

NetBSD 8 is in beta and no release date has been announced yet.  I would expect
NetBSD 6 support to be dropped when NetBSD 8 comes out.

Do we need to support NetBSD 6 given it's age and lack of complete c99 support?

Thanks,
-Matt