+## Functions.
+AC_CHECK_FUNC([prlimit], [have_prlimit=yes], [have_prlimit=no])
+AM_CONDITIONAL([HAVE_PRLIMIT], [test $have_prlimit = yes])
+
+## Processor type.
+case "$host_cpu" in i?86 | x86_64) x86=yes;; *) x86=no;; esac
+AM_CONDITIONAL([X86], [test $x86 = yes -a $GCC = yes])
+