Hi,

Seth Alves found a bug in the reference implementation for
string-trim-right.  For the full discussion, please see the thread on
the chicken-hackers mailing list:
http://lists.gnu.org/archive/html/chicken-hackers/2014-01/msg00016.html

Attached you can find a patch against the reference implementation
(ported from the one provided by Seth).

Best wishes.
Mario
--
http://parenteses.org/mario