Horton

Re: power() function in Windows: "value out of range: underflow"

Euler Taveira <euler@timbira.com.br>

View thread View on postgr.es
From: Euler Taveira <euler@timbira.com.br>
To: Huong Dangminh <huo-dangminh@ys.jp.nec.com>
Cc: "pgsql-bugs@lists.postgresql.org" <pgsql-bugs@lists.postgresql.org>, Pg Hackers <pgsql-hackers@postgresql.org>, Akio Iwaasa <aki-iwaasa@vt.jp.nec.com>
Date: 2018-04-10T14:04:17Z
Lists: pgsql-bugs, pgsql-hackers 
2018-04-10 5:30 GMT-03:00 Huong Dangminh <huo-dangminh@ys.jp.nec.com>:
> There are some cases that power() function does not work
> correctly with 'NaN' arguments in Windows environment.
> Something like,
>
What is your exact OS version? What is your postgres version? I tested
with Windows 10 (10.0.16299) x64 and couldn't reproduce the error.

> postgres=# select power('NaN',11);
> ERROR:  value out of range: underflow
> postgres=# select power('NaN','NaN');
> ERROR:  value out of range: underflow
> postgres=# select power(11,'NaN');
> ERROR:  value out of range: underflow
>
> In Linux environment, instead of ERROR it returns 'NaN'.
>
Could you show us a simple test case? Print arguments, result and errno.


-- 
   Euler Taveira                                   Timbira -
http://www.timbira.com.br/
   PostgreSQL: Consultoria, Desenvolvimento, Suporte 24x7 e Treinamento

Commits

  1. Revert back-branch changes in power()'s behavior for NaN inputs.

  2. Avoid wrong results for power() with NaN input on more platforms.

  3. Avoid wrong results for power() with NaN input on some platforms.