quad precision on PowerPC?

Vincent Lefevre vincent+gcc@vinc17.org
Fri May 13 10:20:00 GMT 2011


On 2011-05-13 11:38:22 +0200, Axel Freyn wrote:
> Hi Vincent,
> On Fri, May 13, 2011 at 11:29:46AM +0200, Vincent Lefevre wrote:
> > https://www-304.ibm.com/support/docview.wss?rs=2030&uid=swg21245006
> > says:
> > 
> >     GCC versions 4.0 and higher support 128-bit quad precision
> >     floating point values. The XL compilers now provide the
> >     -qfloat=gcclongdouble option to be compatible with GCC's
> >     representation of 128-bit quad precision floating point
> >     values.
> > 
> > Anyone knows how to enable it?
> > 
> > By default, I just get the double-double representation (yielding
> > 106-bit precision).
> the gcc online-docs say
> http://gcc.gnu.org/onlinedocs/gcc/Floating-Types.html
> "Not all targets support additional floating point types. __float80 and
> __float128 types are supported on i386, x86_64 and ia64 targets."
> (but I never tried it on PowerPC)

Still, __float128 isn't a long double as said in the note above.
I now wonder whether the note is correct.

-- 
Vincent Lefèvre <vincent@vinc17.net> - Web: <http://www.vinc17.net/>
100% accessible validated (X)HTML - Blog: <http://www.vinc17.net/blog/>
Work: CR INRIA - computer arithmetic / Arénaire project (LIP, ENS-Lyon)



More information about the Gcc-help mailing list