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Date: Thu, 4 Mar 2021 16:52:23 +0100
To: cygwin@cygwin.com
Subject: Re: segfault on 32bit cygwin snapshot
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From: Corinna Vinschen via Cygwin <cygwin@cygwin.com>
Reply-To: cygwin@cygwin.com
Cc: Corinna Vinschen <corinna-cygwin@cygwin.com>
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On Mar  4 18:05, Takashi Yano via Cygwin wrote:
> Hi Corinna,
> 
> On Wed, 3 Mar 2021 12:00:25 +0100
> Corinna Vinschen wrote:
> > [Ping Mark Geisert]
> > 
> > Is there a way around that?  I'm not quite sure, so let's brain storm
> > a bit, ok?
> > 
> > - One thing we could try is to remove the above code, but add a python
> >   hack to dlsym instead.  This would let the "old" DLLs work again as
> >   before and for python we could add a hack to dlsym, along these lines:
> > 
> >     if (CYGWIN_VERSION_CHECK_FOR_UNAME_X
> >     	&& modulehandle == cygwin1.dll
> > 	&& strcmp (symname, "uname"))
> >       symname = "uname_x";
> > 
> > Thoughts?  Other ideas?
> 
> It sounds very reasonable to me to deal with it within dlsym(),
> as the problem arises from the use of dlsym(). However, what
> happens if newly built .exe is linked to old dll which calls
> uname() via dlsym()? I am not sure whether there are such dlls.

We simply can't fix that, because we don't have a Cygwin-specific
per-DLL information block as we have for EXEs.  There's no way to
workaround that problem.


Corinna
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