Index: autogen-5.18.12/agen5/guile-iface.h
===================================================================
--- agen5/guile-iface.h
+++ agen5/guile-iface.h
@@ -9,16 +9,13 @@
 # error AutoGen does not work with this version of Guile
   choke me.
 
-#elif GUILE_VERSION < 201000
+#else
 # define AG_SCM_IS_PROC(_p)           scm_is_true( scm_procedure_p(_p))
 # define AG_SCM_LIST_P(_l)            scm_is_true( scm_list_p(_l))
 # define AG_SCM_PAIR_P(_p)            scm_is_true( scm_pair_p(_p))
 # define AG_SCM_TO_LONG(_v)           scm_to_long(_v)
 # define AG_SCM_TO_ULONG(_v)          ((unsigned long)scm_to_ulong(_v))
 
-#else
-# error unknown GUILE_VERSION
-  choke me.
 #endif
 
 #endif /* MUTATING_GUILE_IFACE_H_GUARD */
Index: autogen-5.18.12/configure
===================================================================
--- configure
+++ configure
@@ -14198,7 +14198,7 @@ $as_echo "no" >&6; }
 		PKG_CONFIG=""
 	fi
 fi
-  _guile_versions_to_search="2.0 1.8"
+  _guile_versions_to_search="2.2 2.0 1.8"
   if test -n "$GUILE_EFFECTIVE_VERSION"; then
     _guile_tmp=""
     for v in $_guile_versions_to_search; do
Index: autogen-5.18.12/config/guile.m4
===================================================================
--- config/guile.m4
+++ config/guile.m4
@@ -61,7 +61,7 @@
 #
 AC_DEFUN([GUILE_PKG],
  [PKG_PROG_PKG_CONFIG
-  _guile_versions_to_search="m4_default([$1], [2.0 1.8])"
+  _guile_versions_to_search="m4_default([$1], [2.2 2.0 1.8])"
   if test -n "$GUILE_EFFECTIVE_VERSION"; then
     _guile_tmp=""
     for v in $_guile_versions_to_search; do