Re: [Help-gsl] Double vs Long Double

[Brian Gough]

At Thu, 4 Oct 2007 20:53:28 +0000 (GMT),
dave wrote:
> I tried setting GSL_IEEE_MODE='extended-precision' and the OpenBSD version
> dumped core after printing an error message.
> 
> gsl: fp-openbsd.c:41: ERROR: OpenBSD only supports default precision rounding
> Default GSL error handler invoked.
> Abort trap (core dumped)
> 
> This also happened with GSL_IEEE_MODE='double-precision'. It appears that this
> variable affects only rounding mode. It would be extremely handy if this 
> technique
> could be used to switch between 80 bit temporary real  (8087) math and 64 bit 
> xmm math
> operations.

You can call the assembly instructions directly, details are in my
book:

http://www.network-theory.co.uk/docs/gccintro/gccintro_70.html

-- 
Brian Gough