+# check for 3 typedefs added in Guile 1.9
+save_CXXFLAGS="$CXXFLAGS"
+CXXFLAGS="$GUILE_CFLAGS $CXXFLAGS"
+AC_CHECK_TYPES([scm_t_hash_fold_fn, scm_t_hash_handle_fn],
+ [AC_DEFINE(HAVE_GUILE_HASH_FUNC)], [],
+ [#include <libguile.h>])
+AC_CHECK_TYPES([scm_t_subr],
+ [AC_DEFINE(HAVE_GUILE_SUBR_TYPE)], [],
+ [#include <libguile.h>])
+CXXFLAGS="$save_CXXFLAGS"