ifdef([m4_version_compare],
[m4_if(m4_version_compare(m4_defn([AC_ACVERSION]), [$1]), -1, [$3], [$2])],
[CF_ACVERSION_COMPARE(
ifdef([m4_version_compare],
[m4_if(m4_version_compare(m4_defn([AC_ACVERSION]), [$1]), -1, [$3], [$2])],
[CF_ACVERSION_COMPARE(