Preferentially use C99 function fpclassify to classify floating point numbers as finite/infinite/NaN.  However, don't use C99 function isfinite since it doesn't seem to work on Cygnus. Now we get the correct results on Cygwin, except that log(-1.0) doesn't give a NaN, so that test still fails.  (0/0 does give a NaN, but MIL doesn't let us calculate that: it returns nil instead.)
Preferentially use C99 function fpclassify to classify floating point
numbers as finite/infinite/NaN.  However, don't use C99 function
isfinite since it doesn't seem to work on Cygnus.
Now we get the correct results on Cygwin, except that log(-1.0)
doesn't give a NaN, so that test still fails.  (0/0 does give a NaN,
but MIL doesn't let us calculate that: it returns nil instead.)

zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb