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Re: [rfa(arm)/rfc] Eliminate HOST_{FLOAT,DOUBLE,...}_FORMAT
> Date: Fri, 29 Jun 2001 11:17:23 -0400
> From: Andrew Cagney <ac131313@cygnus.com>
> >
> > You could lose information if the original value's bit pattern is not
> > a valid FP number. Does floatformat_to_doublest handle these
> > situations 110% correctly? I see at least one FIXME comment in the
> > code there.
>
>
> At present this loss happens randomly depending on the host / target
> combination. I would prefer GDB to at least have slightly more
> consistent behavour.
I agree with the goal, but I don't think we could explain to users of
native debuggers that they have NaN's being converted to Inf's in the
name of consistency ;-)
> /* Note that if exponent indicates a NaN, we can't really do anything useful
> (not knowing if the host has NaN's, or how to build one). So it will
> end up as an infinity or something close; that is OK. */
Perhaps we should allow each native platform to provide a function
that produces a NaN for every FP type it supports? Then utils.c won't
need to bother about doing things it doesn't know about.