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Date:	Thu, 21 Feb 2002 08:56:28 +0200 (IST)
From:	Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
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To:	Charles Sandmann <sandmann AT clio DOT rice DOT edu>
cc:	djgpp AT delorie DOT com
Subject:	Re: RHIDE debugger fails to start on board without floating point unit
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On Wed, 20 Feb 2002, Charles Sandmann wrote:

> You can't use debuggers with an emulator if I remember correctly..  Does your 
> program use floating point?  If it does not, this might work:
>  1) SET 387=N
>  2) Rename EMU387.DXE so it's not found.
> See if you can debug.  I believe this should avoid all FP instructions.

Unfortunately, I don't think it will work because the debugger tries to 
save the x87 state before it runs the debuggee, even if there's no x87 
(because the emulator state needs also to be saved).  Without emu387.dxe, 
the code in the debugger which does that will bomb.

> If it does use floating point I think you are stuck, since the emulator 
> doesn't know how to handle floating traps in a different address space.

It doesn't need to, I think: the debug support in libdbg.a should do the 
necessary footwork for it to be transparent.  This should really be fixed 
some day.

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