--- /dev/null
+#serial 3
+
+dnl From Paul Eggert.
+
+AC_DEFUN([jm_AC_TYPE_UNSIGNED_LONG_LONG],
+[
+ AC_CACHE_CHECK([for unsigned long long], ac_cv_type_unsigned_long_long,
+ [AC_TRY_LINK([unsigned long long ull = 1; int i = 63;],
+ [unsigned long long ullmax = (unsigned long long) -1;
+ return ull << i | ull >> i | ullmax / ull | ullmax % ull;],
+ ac_cv_type_unsigned_long_long=yes,
+ ac_cv_type_unsigned_long_long=no)])
+ if test $ac_cv_type_unsigned_long_long = yes; then
+ AC_DEFINE(HAVE_UNSIGNED_LONG_LONG, 1,
+ [Define if you have the unsigned long long type.])
+ fi
+])