rem: MYSQL_RES *r = MYSQL_RES_UNBOX(obj); mysql_free_result(r);
add: if (!SCM_FALSEP(Scm_ForeignPointerAttrGet(SCM_FOREIGN_POINTER(obj), sym_closed, SCM_FALSE))) { MYSQL_RES *r = MYSQL_RES_UNBOX(obj); mysql_free_result(r); }
context: static void mysql_res_cleanup(ScmObj obj){    MYSQL_RES *r = MYSQL_RES_UNBOX(obj);    mysql_free_result(r);}