glibc 2.8, MacOS X 10.5, Solaris 10, and others.
@item
The type @code{va_list} is missing on some platforms:
-glibc 2.8, OpenBSD 4.0, Solaris 10, and others.
+glibc 2.8, OpenBSD 4.0, Solaris 11 2010-11, and others.
@item
Some platforms provide a @code{NULL} macro that cannot be used in arbitrary
expressions: