Re: BUG #6233: pg_dump hangs with Access Violation C0000005 - Mailing list pgsql-bugs

From Alvaro Herrera
Subject Re: BUG #6233: pg_dump hangs with Access Violation C0000005
Date
Msg-id 1317784584-sup-6771@alvh.no-ip.org
Whole thread Raw
In response to Re: BUG #6233: pg_dump hangs with Access Violation C0000005  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: BUG #6233: pg_dump hangs with Access Violation C0000005  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-bugs
Excerpts from Tom Lane's message of mar oct 04 22:04:29 -0300 2011:
> "Pavel Holec" <holec@email.cz> writes:
> > In the meantime I tried debug in msvc2005 (Win7/32) and
> > free(funcsig); in pg_dump.c line 7510 cause
> > _ASSERTE(_CrtIsValidHeapPointer(pUserData)); in dbgheap.c line 1252
> > * If this ASSERT fails, a bad pointer has been passed in. It may be
> > * totally bogus, or it may have been allocated from another heap.
> > * The pointer MUST come from the 'local' heap.
>
> > If I comment free(funcsig); and next one free(funcsig_tag); pg_dump works fine.
>
> 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...)
>
> However, the flaw in that explanation is that it would basically mean
> pg_dump doesn't work at all on Windows, at least not if you have any
> user-defined functions, and probably some other cases too because there
> seem to be multiple instances of the dubious coding.  It's a bit hard to
> believe that nobody's noticed that before.

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

It's something like this, no?
http://msdn.microsoft.com/en-us/library/ff542911(v=VS.85).aspx

--
Álvaro Herrera <alvherre@commandprompt.com>
The PostgreSQL Company - Command Prompt, Inc.
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