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Date: Wed, 24 Nov 2004 18:19:00 -0000
From: Andrew Haley <aph@redhat.com>
To: Richard Henderson <rth@redhat.com>
Cc: "Aaron W. LaFramboise" <aaronavay62@aaronwl.com>,
   Danny Smith <dannysmith@users.sourceforge.net>, gcc@gcc.gnu.org,
   Cygwin <cygwin@cygwin.com>, mingw-dvlpr <mingw-dvlpr@lists.sourceforge.net>
Subject: Re: stdcall lib functions with exception throwing callbacks vs Dwarf2 EH
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Richard Henderson writes:
 > On Wed, Nov 24, 2004 at 02:51:35AM -0600, Aaron W. LaFramboise wrote:
 > > Is there a way to have the DW2 unwinder call some particular function,
 > > for eg, if the previous frame was not compiled with -fexceptions, rather
 > > than just crashing?  Is this what MD_FALLBACK_FRAME_STATE_FOR is for?
 > 
 > Yes, sortof.  I don't know if you can make it do what you want, exactly.
 > 
 > > Other Windows compilers are able to handle this condition.
 > 
 > If you want to be able to handle this, I recommend that you NOT use dwarf2.

DWARF2 unwinder data is required by Java for things other than just
throwing exceptions.  If it's possible to create a
MD_FALLBACK_FRAME_STATE_FOR that can unwind through SEH frames -- and
I believe it is -- we should do so.

Andrew.