Message-ID: <475EA9FD.9000706@emolecules.com>
Date: Tue, 11 Dec 2007 07:17:17 -0800
From: Craig James <craig_james@emolecules.com>
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To: Alvaro Herrera <alvherre@alvh.no-ip.org>
CC: pgsql-performance@postgresql.org
Subject: Re: libgcc double-free, backend won't die
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	<472978BE.9@hagander.net> <4729B1E9.2080306@gmail.com>
	<475E4133.5080009@emolecules.com>
	<20071211112128.GB4708@alvh.no-ip.org>
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Alvaro Herrera wrote:
> Craig James wrote:
> 
>> Here is my guess -- and this is just a guess.  My functions use a
>> third-party library which, of necessity, uses malloc/free in the
>> ordinary way.  I suspect that there's a bug in the Postgres palloc()
>> code that's walking over memory that regular malloc() allocates.  The
>> third-party library (OpenBabel) has been tested pretty thoroughly by
>> me an others and has no memory corruption problems.  All malloc's are
>> freed properly.  Does that seem like a possibility?
> 
> Not really.  palloc uses malloc underneath.

But some Postgres code could be walking off the end of a malloc'ed block, even if palloc() is allocating and deallocating correctly.  Which is why I was hoping to use valgrind to see what's going on.

Thanks,
Craig