Message-Id: <3.0.5.32.19981221145429.007f2100@ics.u-strasbg.fr>
X-Sender: muller AT ics DOT u-strasbg DOT fr
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Date: Mon, 21 Dec 1998 14:54:29 +0100
To: djgpp-workers AT delorie DOT com
From: Pierre Muller <muller AT cerbere DOT u-strasbg DOT fr>
Subject: debug GDB with itself 
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Reply-To: djgpp-workers AT delorie DOT com


  I wrote some modifications that allow GDB (v4.16) to debug itself :

 the main point was to intercept exception redirection via int 0x31 calls
but at an excpetion to decide (according to the value of the cs selector)
if the exception should be passed to child or treated by the current level

  I also added code in go32targ.c to be able to inspect memory of other
selector

  for instance 
   xx $ss:$esp

can display the value on the current stack even if it is not the
application stack
(that happens a lot when debuggging GDB with itself !)

  The main reason I did this is that we (FPC development team are working on a
pascal extension for GDB, but I got some weird problems !)

  How should I submit my changes ?

  (for exception handling all is in dbgcom.c
for the xx command it is across several files !)


|\  Pierre Muller    
|/  Institut Charles Sadron  6, rue Boussingault
|\  F 67083 STRASBOURG CEDEX
|/  Phone : (33)(0)3-88-41-40-07  Fax : (33)(0)3-88-41-40-99
|\  e-mail : muller AT ics DOT u-strasbg DOT fr