From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <18daad73cb88cb5f853285318a06c7f6@plan9.bell-labs.com>
From: David Presotto <presotto@closedmind.org>
To: dbailey27@ameritech.net, 9fans@cse.psu.edu
Subject: Re: [9fans] Do the Pool Voodoo like I do
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Date: Thu, 19 Feb 2004 20:07:42 -0500
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You're running past the allocated memory.  'mem user overflow' means that
malloc detected that your program has written past the end of the allocated buffer.
It can do this because it actually may 'overallocate', i.e., allocating more memory
than you asked for.  It puts a predetermined pattern in the extra bytes.  If it
finds  that pattern has been altered, it complains its little ass off.
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Subject: [9fans] Do the Pool Voodoo like I do
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Hey all,
	I'm having a bit of trouble with the malloc
library. I've got an algorithm that dynamically
allocates memory char by char using realloc in
a loop. However, the lib seems to be having some
internal problem. I've got seriously unoptimized
code handling the token stream this algorithm
parses, so there are two cases for the crash below:
	1) my unoptimized code is allocating too much
	    heap and that's causing the panic
	2) there is an internal alloc bug that I'm triggering

Here's the panic info:

mem user overflow
pool sbrkmem block d9a0
hdr 0a110c09 00000020 000023b5 00001f3e 0023ff24 caf0f1fe
tail 0a110c09 00000020 000023b5 00001f3e 0023ff24 caf0f1fe | ef1500be 00000020
user data 00 3e 1f 00  00 24 ff 23 | 00 fe f1 f0  ca be 00 15
panic: pool panic
8.out 703: suicide: sys: trap: fault read addr=0x0 pc=0x000065fb
apple%

Any ideas? More info provided on request.

Don (north_)
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