unsetenv etc.: port to Solaris 11 + GNU Emacs * lib/canonicalize-lgpl.c, lib/getaddrinfo.c, lib/getdelim.c: * lib/glob.c, lib/random_r.c, lib/setenv.c, lib/tsearch.c: * lib/unsetenv.c (_GL_ARG_NONNULL): Define before including <config.h>. GNU Emacs's <config.h> includes <stdlib.h> (which is not a great idea but is too painful to fix right now), and without this gnulib change <stdlib.h> was defining _GL_ARG_NONNULL incorrectly when compiling unsetenv.c on Solaris 11. Fix the problem for unsetenv.c, and fix other similar occurrences.

#include <config.h>
#define FCHOWNAT_INLINE _GL_EXTERN_INLINE
#include "openat.h"