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Date: Fri, 01 Aug 2008 08:46:51 -0700
From: Brian Dessent <brian AT dessent DOT net>
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To: Steve Waldo <steven DOT j DOT waldo AT seagate DOT com>
CC: cygwin AT cygwin DOT com
Subject: Re: seg fault produces stackdump with no stack trace
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Steve Waldo wrote:

> but the resulting file contains no stack trace:
> 
> $ cat ResourceMgr.exe.stackdump
> Exception: STATUS_ACCESS_VIOLATION at eip=00000000

Right there you should see the problem.  eip=0 means your program has
followed a null pointer and wandered off into lala land, so you
shouldn't be surprised that this unwinder can't do anything, as this
probably triggers an internal "stop, something's wrong" check because
eip=0 cannot possibly be a correct frame.

The unwinder used here is very primitive, it only knows how to unwind a
standard frame layout.  It does not use anything sophisticated like
unwind tables or debug info, and it will be totally stymied if a frame
uses FPO/-fomit-frame-pointer style optimizations where the return
address is not at 4(%ebp).

Brian

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