kern/154073: [libz] libz causes perl to exit on signal 11

[Всеволод Новиков]

The following reply was made to PR kern/154073; it has been noted by GNATS.

From: =?UTF-8?B?0JLRgdC10LLQvtC70L7QtCDQndC+0LLQuNC60L7Qsg==?=
 <novikov at doroga.tv>
To: bug-followup at FreeBSD.org, azhegalov at gmail.com
Cc:  
Subject: Re: kern/154073: [libz] libz causes perl to exit on signal 11
Date: Fri, 01 Jul 2011 19:29:46 +0400

 Hi,
 
 We have got the similar problem, seeing stack top identical, on the 
 FreeBSD 8.2-RELEASE (amd64 arch on the 2x Intel Core Quad Xeon platform, 
 chipset Intel 5000p).
 
 The patch provided by Andrey Zonov helps, segfaults disappear.
 
 Looks like the asm version of the longest_match() function has some bug 
 or architecture incompatibility. The error happens not regularly, 
 probably in very special case. We got it using PyQt to paint jam tiles 
 basing on our data, only sometimes - after 5-30 minutes of intensive 
 continuous painting, independently on using multi-thread features. The 
 (pseudo)stack was always looking like:
 
 longest_match()
 deflate_slow()
 deflate()
 --- libpng functions ---
 --- Qt functions ---
 --- PyQt functions ---
 --- Python interpreter ---
 
 Regards,
 Vsevolod Novikov