Groveler and HUGE_VAL

[Zach]

I am trying to grovel the value of HUGE_VAL from math.h.  This:

(constant (huge-val "HUGE_VAL") :type double-float)

doesn't work, presumably because HUGE_VAL isn't a proper float on my system
(but rather some special positive infinity double float).  I get this error:

The value NLOPT::INF is not of type REAL.

I need to use HUGE_VAL in the arguments in my NLOpt bindings (hence the
package name in NLOPT::INF, though I don't think I even typed INF into the
system).  I believe that I can't use, say, most-positive-double-float, as
there is special behavior when the value HUGE_VAL is used, i.e. it isn't
just a large number.

Interestingly, I can grovel HUGE_VAL as an integer with value
18446744073709551615 which, presumably, if I used the ieee-floats system:

(ieee-floats:decode-float64 18446744073709551615) == HUGE_VAL

However, I'm not sure of that and that form naturally produces an overflow
error.  This is a value that cannot actually be represented as a float,
after all.  Anyway, I'm not sure that this helps me as I have to pass it to
a function that expects a double (actually I pass it as an element in an
array of doubles that gets passed to the function):

nlopt_result nlopt_set_lower_bounds(nlopt_opt opt, const double* lb);

So, I think I need to hold the sizeof(double) bytes in memory (whatever the
value of HUGE_VAL is) so that I can write it out to an array later.  This
is doable, but I am having trouble figuring out the syntax to have the
groveler automate the task of getting those sizeof(double) bytes in the
first place.

Is there a way to deal with this?  Even better, is there a way that CFFI
makes this much simpler so I can just pass define whatever holds HUGE_VAL
as an opaque object that can be used as a double?  Even better yet, the
value of HUGE_VAL provided by CFFI already and I am just not seeing it?

Thanks for reading, any help is appreciated,
Zach
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