infinityp and nanp require CFFI.

[j3pic]

I purportedly implemented a feature allowing the use of Lisp-Binary without CFFI. But I forgot about the fact that nanp and infinityp are just front-ends to their C counterparts. Also, the constants +inf, -inf, and quiet-nan are created by casting bit-patterns to float via CFFI.

In CCL, I avoid some of the problem by using CCL's extended constants. Newer versions of SBCL have constants for infinity, too, but I don't use them because SBCL didn't have them when I wrote the feature. I could begin using them now.

SBCL does not have a constant for NaN, but it does have sb-ext:float-nan-p. So I could avoid using C's isnan(), but I have no way to create one without CFFI.