* bignum.c (bigsub_int): Use bdigit_roomof.
  (bigadd_int): Ditto.
  (bigand_int): Ditto.
  (bigor_int): Ditto.
  (bigxor_int): Ditto.



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@41529 b2dd03c8-39d4-4d8f-98ff-823fe69b080e