Re: BUG #6233: pg_dump hangs with Access Violation C0000005

-----Original Message-----
From: Tom Lane [mailto:tgl(at)sss(dot)pgh(dot)pa(dot)us]
Sent: Wednesday, October 05, 2011 6:07 AM
To: Alvaro Herrera
Cc: Pavel Holec; 'Craig Ringer'; Pg Bugs
Subject: Re: [BUGS] BUG #6233: pg_dump hangs with Access Violation C0000005

Alvaro Herrera <alvherre(at)commandprompt(dot)com> writes:
> Excerpts from Tom Lane's message of mar oct 04 22:04:29 -0300 2011:
>> Hmm. I can see how that would happen if you're using one of the
>> Windows environments wherein malloc's done inside libpq have to be
>> free'd inside libpq. (The PQExpBuffer support code is in libpq...)

> Isn't this the kind of thing that you have to enable explicitly?

>>> I'm looking at our docs for PQfreemem:

>>> Frees memory allocated by libpq, particularly PQescapeByteaConn,
>>> PQescapeBytea, PQunescapeBytea, and PQnotifies. It is
>>> particularly important that this function, rather than free(),
>>> be used on Microsoft Windows. This is because allocating memory
>>> in a DLL and releasing it in the application works only if
>>> multithreaded/single-threaded, release/debug, and static/dynamic
>>> flags are the same for the DLL and the application. On
>>> non-Microsoft Windows platforms, this function is the same as
>>> the standard library function free().

>>> I have no idea how accurate or complete that third sentence is; but
perhaps the OP is trying to use a libpq.dll that was built separately from
his pg_dump executable?

>>> regards, tom lane

Yes, this is the problem. libpq.dll I have built in VC6. With original I had
problem with msvcr80.dll and WinSxS because my end client app is also from
VC6 and I can't prepare redist msvcr for end user. Can you advice me how to
do it?

Pavel Holec