Bug: https://bugs.gentoo.org/884405
--- a/ldap.c
+++ b/ldap.c
@@ -201,7 +201,7 @@ rb_ldap_hash2mods (VALUE self, VALUE op, VALUE hash)
   VALUE tmp;
 
   tmp = rb_assoc_new (op, rb_ary_new ());
-  rb_iterate (rb_each, hash, rb_ldap_hash2mods_i, tmp);
+  rb_iterate (rb_each, hash, (rb_block_call_func_t)rb_ldap_hash2mods_i, tmp);
 
   return rb_ary_entry (tmp, 1);
 }