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 a minus zero argument on some platforms: OSF/1 5.1.

Portability problems not fixed by Gnulib: