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Date: Sat, 18 Jul 2009 11:25:11 -0400
From: Christopher Faylor <cgf-use-the-mailinglist-please AT cygwin DOT com>
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Subject: Re: fun? with libsigsegv
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On Sat, Jul 18, 2009 at 05:16:51AM -0600, Eric Blake wrote:
>So I see several possibilities:
>[snip]

My point, which I don't think you addressed in your long explanation, is
that there doesn't seem to be any "alternate stack" stuff going on in
the Windows code.  Therefore, it seems like you could just rely on linux
signal handling to get the same level of behavior under Cygwin that you
currently get with the library.  The problem is that, although configure
seems to be ok with a missing sigaltstack function, and some of the code
tries to work around its lack, there are still lots of places which
assume that if you're on UNIX you must have this function.

libaltstack is doing something dangerous by assuming that it knows what
Cygwin is doing with SEH.  I don't think that it should ever be used on
Cygwin in its current incarnation.

cgf

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