Marc Nieper-Wißkirchen wrote:
> I could reformulate my question to: "Is there a way to produce a (quiet)
> NaN that won't occur as a result of the C library functions?"
There are 2^51 possible quiet NaNs [1]. I would guess that the hardware and
libc functions produce only a small portion of this s
; > find it: Does Gnulib offer a way to store a signaling NaN in a memory
> > location (if supported by the platform)
>
> It doesn't, because quiet NaNs are easier to work with.
>
> > The forthcoming C2x standard will have FLT_SNAN, DBL_SNAN, and LDBL_SNAN,
> >
ming C2x standard will have FLT_SNAN, DBL_SNAN, and LDBL_SNAN,
> but before that there doesn't seem to be a portable way to get signaling
> NaNs.
... indeed, when you have a non-optimizing compiler, how to prevent the
compiler from generating instructions that produce a floating-point excep
ndard will have FLT_SNAN, DBL_SNAN, and LDBL_SNAN,
but before that there doesn't seem to be a portable way to get signaling
NaNs.
In case the following problem is easier: What I really need is a bit
pattern for a double that won't be returned by the usual floating-point
functions.
Thanks,
Marc
