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Date: Fri, 07 Sep 2007 07:19:20 -0700
From: Brian Dessent <brian AT dessent DOT net>
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Subject: Re: Slowness problem due to  sjlj-exceptions for Octave
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Dave Korn wrote:

>   Right, so IOW, the SEH support does all the required unwinding for us.
> Ultimately I guess that's the only solution that's going to be both complete
> and correct.  (The only other thing I could even imagine would be some kind of
> hideous .pdb abuse using the M$ official symbol files to extract the frame and
> FPO information for frames in API functions...)

Well, assuming that none of these foreign frames do any kind of
-fomit-frame-pointer style optimizations, it should be possible to
implement a fallback unwinder that simply ignores the frame and advances
one frame up and resumes the table-based unwinding.  And that's what (I
thought) the recent w32-unwind.h contribution in 4.3 does, but I could
be wrong.

Brian

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