9.872 round

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

Gnulib module: round or round-ieee

Portability problems fixed by either Gnulib module round or round-ieee:

• This function is missing on some platforms: FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, older IRIX 6.5, OSF/1 4.0, Solaris 9, MSVC 9, Interix 3.5.
• This function is not declared on some platforms: glibc 2.8, IRIX 6.5, OSF/1 5.1.
• This functions returns a wrong result for x = 1/2 - 2^-54 on some platforms: NetBSD 3.0, AIX 7.1.

Portability problems fixed by Gnulib module round-ieee:

• This function returns a positive zero for an argument between -0.5 and 0 on some platforms: AIX 7.1, OSF/1 5.1.
• This function returns a positive zero for a minus zero argument on some platforms: OSF/1 5.1.

Portability problems not fixed by Gnulib: