| This SRFI regards +nan.0 as a real number whose value is so
 | indeterminate that it might represent any real number within the
 | closed interval [-inf.0,+inf.0].

That sentence implies that (<= -inf.0 +nan.0 +inf.0).

But that is not true in IEEE-754 arithmetic as compiled by gcc running
on an Intel(R) Pentium(R) 4 CPU.