BN_R_DIV_BY_ZERO
BNerror(BN_R_DIV_BY_ZERO);
{ERR_REASON(BN_R_DIV_BY_ZERO) , "div by zero"},
ERR_put_error(ERR_LIB_BN, BN_F_BN_USUB, BN_R_DIV_BY_ZERO,