Date:	Mon, 15 Jul 1996 13:47:26 +0200 (IST)
From:	Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
To:	djgpp-workers AT delorie DOT com
Cc:	Morten Welinder <terra AT diku DOT dk>
Subject:	Debuggers under Windows
Message-Id:	<Pine.SUN.3.91.960715133313.13725E-100000@is>
Mime-Version:	1.0

I made another attempt to solve the GDB bug under Windows.  I didn't 
succeed, but I learned something alarming: it's something generic with 
all DJGPP debuggers that doesn't work there, not only GDB!  (Well, I 
actually only tested with GDB and FSDB.)

To reiterate: the problem is that when you set a breakpoint, GDB tells 
that the debugger got SIGSEGV.  The FAQ suggests using FSDB under 
Windows, but now I know that this is only correct if you never set more 
than 4 breakpoints--because FSDB uses debug registers for the first 4 
breakpoints, so it seems.  ANY breakpoint that is set by writing the CCh 
opcode (Int 03) seems to not work under Windows, in either GDB or FSDB.  
Both the debuggers get Exception 0Dh with an error code of 80000000h 
(does that error code mean anything?).

Another thing that I saw is that the address where Exception 0Dh happens 
is NOT the address where the breakpoint was set, but somewhat after that.

If anybody has any clue as to where to look further, please tell me.  
I've checked all the code around the place where the breakpoint is set 
and didn't find anything that even remotedly seems suspicious.

Is there any special setup that should be done when using Int 03 under 
Windows?

And btw, does GDB breakpoints work under Win95?

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