Strange behaviour -- app starts only with --debugmsg+snoop

[Max]

AutoCAD again !
After finally R14 runs fine, i'm trying with AutoCAD 2000.
Setup goes ok (besides usual VBA problem).
Starting with  'wine acad' gives a very early error of unhandled access 
violation.
I tried to start it with --debugmsg +snoop to see what happened and, surprise, 
app starts up quite good.
It then hangs much later, but that's another problem.
So the question : how it's possible that requesting snoop messages bypasses 
the initial access violation ? I think that snoop adds only a thunk to calls 
on native dlls.... 
Any suggestion appreciated !

Regards

Max

[Uwe Bonnes]

> > > > > "Max" == Max  <max(a)veneto.com> writes:

Max> AutoCAD again !  After finally R14 runs fine, i'm trying with
    Max> AutoCAD 2000.  Setup goes ok (besides usual VBA problem).  Starting
    Max> with 'wine acad' gives a very early error of unhandled access
    Max> violation.  I tried to start it with --debugmsg +snoop to see what
    Max> happened and, surprise, app starts up quite good.  It then hangs
    Max> much later, but that's another problem.  So the question : how it's
    Max> possible that requesting snoop messages bypasses the initial access
    Max> violation ? I think that snoop adds only a thunk to calls on native
    Max> dlls....  Any suggestion appreciated !

If I remember right, this behaviour is a sign of "stack smashing", that
means, the stack got overwritten in some place and causes a crash in some
other , mostly unrelated place. Sometimes you can get some hints for the
cause of that error by running with --debugmsg +heap.  That makes things
much slower, but checks the heap on every heap allocation and aborts on the
first encountered error. Then the smashing must be in between the last
allocation and the error. Running with +relay helps you pinpoint.

Bye
-- 
Uwe Bonnes                bon(a)elektron.ikp.physik.tu-darmstadt.de

Institut fuer Kernphysik  Schlossgartenstrasse 9  64289 Darmstadt
--------- Tel. [phone] -------- Fax. [phone] ----------

[Andreas Mohr]

On Sun, Jul 07, 2002 at 10:52:30PM +0200, Max wrote:
> AutoCAD again !
> After finally R14 runs fine, i'm trying with AutoCAD 2000.
> Setup goes ok (besides usual VBA problem).
> Starting with  'wine acad' gives a very early error of unhandled access 
> violation.
> I tried to start it with --debugmsg +snoop to see what happened and, surprise, 
> app starts up quite good.
> It then hangs much later, but that's another problem.
> So the question : how it's possible that requesting snoop messages bypasses 
> the initial access violation ? I think that snoop adds only a thunk to calls 
> on native dlls.... 
No, AFAIK +snoop stuff does some additional "housekeeping" work, like
initializing/correcting stack and stuff.
This crash could probably be caused by
- API functions with wrong number of parameters (in .spec etc)
- buffers uninitialized by Wine's function implementations even though they
  should be
- some other random stack trashing or so

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