> > > which is evidently doing the wrong thing on your platform. What does
> > > your man page for exp() say about error return conventions?
> I checked it twice, I can't find any error in the current sources. I even wrote a test
> program...
> So both methods seem to work. (finite is a function on glibc-2.1 systems)
And that is the problem. I didn't have enough platforms to test on, so
when I improved the code I did so in a way that I would get a better
result on at least my platform (probably RH4.2 or earlier) without
breaking the behavior on other platforms.
So, I test locally for finite() being defined as a macro! But on newer
glibc systems it is a real function, so you are seeing the old
behavior.
A better thing to do would be to define HAVE_FINITE, and to have a
./configure test for it. That should be easy enough; do you have time
to look at it? Then code like
#ifndef finite if (errno == ERANGE)
#else /* infinity implies overflow, zero implies underflow */ if (!finite(*result) || *result == 0.0)
#endif
Could become
...
#if HAVE_FINITE
...
- Thomas
--
Thomas Lockhart lockhart@alumni.caltech.edu
South Pasadena, California
