isinf
=====

POSIX specification:
 http://www.opengroup.org/onlinepubs/9699919799/functions/isinf.html

Gnulib module: isinf

Portability problems fixed by Gnulib:

  * This macro is missing on some platforms: AIX 5.1, IRIX 6.5, OSF/1 5.1, Solaris 11 2011-11.

  * This macro incorrectly yields true for some long double arguments, on some platforms: OpenBSD 4.9/x86 (pseudo-Infinity).

Portability problems not fixed by Gnulib: