Re: snprintf causes regression tests to fail

From: Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us>
To: Nicolai Tufar <ntufar(at)gmail(dot)com>
Cc: Magnus Hagander <mha(at)sollentuna(dot)net>, pgsql-hackers(at)postgresql(dot)org, pgsql-hackers-win32(at)postgresql(dot)org
Subject: Re: snprintf causes regression tests to fail
Date: 2005-03-01 04:54:42
Message-ID: 200503010454.j214sg524406@candle.pha.pa.us
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers pgsql-hackers-win32

Nicolai Tufar wrote:
> Regression test diff is attached.
> It fails on the following tests:
> int8
> subselect
> union
> sequence
>
> It fails to display correctly number "4567890123456789".
> In output is shows "-869367531". Apparent overflow or
> interpreting int8 as int4.
>
> while rewriting snprintf() I did not touch the actual functions
> that convert number to ASCII digit string. In truth, if you
> force PostgreSQL to use snprintf.c without my patch applied
> it produces the same errors.
>
> What can be wrong? GCC bug? The one I use is:
> gcc.exe (GCC) 3.3.1 (mingw special 20030804-1)

I can confirm your failure in current sources on Win32:

template1=# create table test(x int8);
CREATE TABLE
template1=# insert into test values ('4567890123456789');
INSERT 17235 1
template1=# select * from test;
x
------------
-869367531
(1 row)

and it knows it is a large number:

template1=# select * from test where x > 1000::int8;
x
------------
-869367531
(1 row)
template1=# select * from test where x < 1000::int8;
x
---
(0 rows)

I am going to add some debugs to see what is being passed to *printf().

--
Bruce Momjian | http://candle.pha.pa.us
pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 359-1001
+ If your life is a hard drive, | 13 Roberts Road
+ Christ can be your backup. | Newtown Square, Pennsylvania 19073

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Robert Treat 2005-03-01 05:32:43 mysterious log output
Previous Message Greg Sabino Mullane 2005-03-01 02:47:02 Re: Development Plans

Browse pgsql-hackers-win32 by date

  From Date Subject
Next Message Bruce Momjian 2005-03-01 05:55:20 Re: snprintf causes regression tests to fail
Previous Message Bruce Momjian 2005-03-01 00:38:39 Re: Thread-safe snprintf() vsnprintf() and printf()