Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!uupsi!sunic!news.funet.fi!funic!nic!vinsci
From: vinsci@nic.funet.fi (Leonard Norrgard)
Newsgroups: comp.sys.amiga.programmer
Subject: fun device debugging
Message-ID: <VINSCI.91May27155812@nic.nic.funet.fi>
Date: 27 May 91 13:58:12 GMT
Sender: vinsci@nic.funet.fi (Leonard Norrgard)
Distribution: comp
Organization: Soft Service, Inc.
Lines: 21

The device being debugged is "localser.device" a little hack to
connect to communications programs on one machine to each other, one
opening unit 0 and the other unit 1.
  After the more trivial bugs were found, there is this really fun one
left. Symptoms: When the comm software exits, we have major output
from enforcer and memmung (this being on a 68030 machine). First
access is to $deadbeef, yes, dereferring of freed memory, but how and
where, not to ask about why...?
  The interesting thing is that if I within the comm software give up
on the serial port first, then from a shell issue flushlibs (causes
localser and its unit processes to go away from memory), then exit,
everything is fine. This first lead me to beleive that there was
something wrong with the _LibClose/_LibExpunge interaction, but... I
think I've checked it all. The compiler used is SAS/C 5.10a, and we
found one bug related to creating libraries with blink (the fd file
must have an odd number of entries, or the last vector never gets
initialized...).

So, any similar cases seen before?

-- Leonard