Never pass a leading + to mpz_set_string, parse_integer (). src/ChangeLog addition: 2011-05-01 Aidan Kehoe <kehoea@parhasard.net> * lread.c (parse_integer): GMP's mpz_set_string deals with a leading plus badly, make sure it never sees one coming from this function. tests/ChangeLog addition: 2011-05-01 Aidan Kehoe <kehoea@parhasard.net> * automated/lisp-reader-tests.el: If the bignum feature is available, check that a leading plus sign is treated correctly when reading bignum integers.