Message-ID: <41542B6B.3080607@dunslane.net>
Date: Fri, 24 Sep 2004 10:12:59 -0400
From: Andrew Dunstan <andrew@dunslane.net>
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To: Thomas Hallgren <thhal@mailblocks.com>
Cc: pgsql-hackers@postgresql.org
Subject: Re: Use of zlib
References: <ciuafp$n4u$1@sea.gmane.org>
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Thomas Hallgren wrote:

> Problem:
> PL/Java use a JVM. On some platforms and with some JVM's (Sun's in 
> particular) a libzip.so is bundled that contains a 1.1.3 version of 
> functions also provided in zlib (why they do this is beyond me, but 
> they do so I'll have to live with it). PostgreSQL is linked with zlib 
> by default. This resuls in a conflict which resuls in a JVM crash.
>
> I can circumvein this crash by using LD_PRELOAD to force a load of the 
> JVM bundled libzip.so but I suspect that might result in a crash as 
> soon as PostgreSQL calls on zlib to do something. It's of course 
> possible to configure postgresql with --without-zlib also provided you 
> have accesst o the source.
>
> Question:
> From what I can understand from the documentation, the only utility in 
> PostgreSQL that actually uses zlib is pg_dump? If so, why is the 
> postgres process linked with -lz?
>
>

I did a small experiment by installing binutils 2.15 and adding 
-Wl,--as-needed to the LDFLAGS, as Tom had suggested might be useful.

This seemed to work quite well and trimmed back the needed libs quite a 
bit. However, when you configure --with-openssl, libz is again linked in.

Not sure where that leaves us.

cheers

andrew