7.25 math.h

POSIX specification:
http://www.opengroup.org/onlinepubs/9699919799/basedefs/math.h.html

Gnulib module: math

Portability problems fixed by Gnulib:

• The conversion from int to long double in incorrect on some platforms: glibc 2.7 on Linux/SPARC64.
• The macro NAN is not defined on some platforms: OpenBSD 4.0, AIX 5.1, IRIX 6.5, OSF/1 5.1.
• The macro NAN is not exposed outside of C99 compilation on some platforms: glibc.
• The macros NAN and HUGE_VAL expand to a function address rather than a floating point constant on some platforms: Solaris 10.

Portability problems not fixed by Gnulib:

• NAN is not a compile time constant with some compilers: OSF/1 with Compaq (ex-DEC) C 6.4.
• The macro or variable math_errhandling is not defined on some platforms: glibc 2.11, OpenBSD 4.9, NetBSD 5.1, UP-UX 11, IRIX 6.5, OSF/1 5.1, Cygwin 1.7.9, mingw, MSVC 9.