From: Jorgen Loland
Date: January 10 2011 12:02pm
Subject: Re: bzr commit into mysql-5.1-bugteam branch (martin.hansson:3520)
 Bug#58207
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On 12/22/2010 03:49 PM, Martin Hansson wrote:
> Jorgen Loland skrev 2010-12-16 12.27:
>> On 12/16/2010 11:16 AM, Martin Hansson wrote:
>>> Jorgen Loland skrev 2010-12-16 10.02:
>>>>
>>>>
>>>> On 12/16/2010 09:21 AM, Martin Hansson wrote:
>>>>> Jorgen Loland skrev 2010-12-15 14.07:
>>>>>> Martin,
>>>>>>
>>>>>> The fix looks good, but the test case in the patch does not give
>>>>>> valgrind warning. Please provide a test case that is fixed by the
>>>>>> patch (e.g., the one reported in the bug). If you violently refuse to
>>>>>> replace this test, you can add one more instead.
>>>>> You did build with BUILD/compile-pentium-valgrind-max, right? If you
>>>>> still don't see it you might try to revert to the same revision as I
>>>>> committed into.
>>>>>
>>>>> Does the test case in the bug report give valgrind warnings but mine
>>>>> doesn't? If they do then that's serious enough, BUT... things actually
>>>>> changed *while* I was working on the bug. First time around, the first
>>>>> test caused a core dump. Then when I pulled the latest changes it
>>>>> didn't, and then two days later it caused a crash again. The bug is
>>>>> that
>>>>> we get a totally runaway pointer, so it's sensitive to just about
>>>>> anything.
>>>>
>>>> I compiled with compile-amd64-valgrind-max.
>>>>
>>>> Without your code changes, the test case in the bug report gives
>>>> valgrind warnings like this:
>>>>
>>>> ==7710== Invalid read of size 1
>>>> ==7710== at 0x4C28E61: memcpy (mc_replace_strmem.c:497)
>>>> ==7710== by 0x76A3C3: create_tmp_table(THD*, TMP_TABLE_PARAM*,
>>>> List<Item>&, st_order*, bool, bool, unsigned long long, unsigned long
>>>> long, char*) (sql_select.cc:10412)
>>>>
>>>> These warnings go away when I apply your fix. The test case you added
>>>> does not give valgrind warning before applying your code changes.
>>>>
>>> Revision number, please.
>>
>> 3524 gleb.shchepa@stripped
>>
> This is strange, I can repeat it just fine in the revision I committed,
> 3524 and 3533. I do suspect you're running on 64 bit, though. Perhaps we
> can work together to find a test case that fails on both architectures?
> I currently don't have a 64 bit box set up. Only one is my mac on which
> valgrind doesn't work.

Yes, I'm running on 64 bit. The original test case seems to fail "correctly" on 
my box.

-- 
Jørgen Løland | Senior Software Engineer | +47 73842138
Oracle MySQL
Trondheim, Norway