9.98 ceil

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

Gnulib module: ceil or ceil-ieee

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

Portability problems fixed by Gnulib module ceil-ieee:

• This function returns a positive zero for an argument between −1 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: