diff -urNp -x '*.orig' postgresql-15.5.org/configure.ac postgresql-15.5/configure.ac
--- postgresql-15.5.org/configure.ac	2023-12-16 01:48:24.301566950 +0100
+++ postgresql-15.5/configure.ac	2023-12-16 01:48:27.689610199 +0100
@@ -19,10 +19,6 @@ m4_pattern_forbid(^PGAC_)dnl to catch un
 
 AC_INIT([PostgreSQL], [15.5], [pgsql-bugs@lists.postgresql.org], [], [https://www.postgresql.org/])
 
-m4_if(m4_defn([m4_PACKAGE_VERSION]), [2.69], [], [m4_fatal([Autoconf version 2.69 is required.
-Untested combinations of 'autoconf' and PostgreSQL versions are not
-recommended.  You can remove the check from 'configure.ac' but it is then
-your responsibility whether the result works or not.])])
 AC_COPYRIGHT([Copyright (c) 1996-2022, PostgreSQL Global Development Group])
 AC_CONFIG_SRCDIR([src/backend/access/common/heaptuple.c])
 AC_CONFIG_AUX_DIR(config)