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From:	Andrew Schulman <andrex AT alumni DOT utexas DOT net>
Subject:	RE: autossh crash with 20050314 and earlier cygwin1.dll
Date:	Wed, 16 Mar 2005 12:07:53 -0500
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> 0065E938  61093A1F  (6112B460, 7974742F, 61120031, 6974616D)
> malloc.cc:3952
> 	  nextchunk = chunk_at_offset(p, size);
> 	  nextsize = chunksize(nextchunk);
> 
> 
>   yeesh.  nasty heap corruption leading to bad nextchunk pointer and an
> exception when it is dereferenced in the attempt to find nextsize.
> happening in a realloc call.  ugly.  it's going to be hard to track down;
> whatever is causing the corruption may be taking place an arbitrary amount
> of time prior to when the exception happens, and not necessarily in the same
> thread either.

Would the job be easier in my case, where I have a repeatable crash?  I 
provided strace output in the earlier thread about my autossh problems, 
but haven't tried using any debug builds of cygwin1.dll.  I'm not 
conversant with debuggers, but I have used gdb before and could work my 
way through it.  Let me know if this would be useful, and how best to go 
about it.

Of course there's no guarantee that my crash and David's have the same 
cause, but they might well and it would be as good a place as any to 
start.


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