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Date: Tue, 12 Sep 2000 14:55:00 +0100
Message-ID: <7767-Tue12Sep2000145500+0100-starksb@ebi.ac.uk>
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From: David Starks-Browning <starksb AT ebi DOT ac DOT uk>
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To: cygwin AT sources DOT redhat DOT com
Subject: Re: problem with dynamic_cast
In-Reply-To: <20000908230049.A21412@cygnus.com>
References: <B0016417505 AT mzdy17 DOT allegro DOT net>
	<20000908124631 DOT C13006 AT cygnus DOT com>
	<20000908230049 DOT A21412 AT cygnus DOT com>

On Friday 8 Sep 00, Chris Faylor writes:
> On Fri, Sep 08, 2000 at 12:46:31PM -0400, Chris Faylor wrote:
> >On Fri, Sep 08, 2000 at 10:18:42AM -0400, Fleischer, Karsten (K.) wrote:
> >>How about including the stub libraries in the distribution, rather than the
> >>symlinks?
> >
> >The reason for the symlinks is that some packages search libc.a and libm.a
> >for symbols.
> >
> >If linking libc.a twice causes problems, then it *is* a bug in either gcc or
> >ld.
> >
> >Mumit had vowed once to fix this problem but then he disappeared...
> 
> Ok, I looked into this.  It is a linker problem.  Specifying -lm or -lc on
> the command line causes ld to put symbols into the import section in improperly
> sorted order.
> 
> This confuses the Windows "dynamic loader" (and I use the term loosely) so that
> certain function calls (namely strcmp and strlen) are not resolved.  So when
> a function in libgcc needs to call strcmp it ends up jumping into unallocated
> memory, causing a SIGSEGV.
> 
> That's the analysis.  I have no idea how to fix this, but I've sent some details
> to DJ in the hopes that he'll be able to do something about this.

Would it be helpful if I put this in the FAQ?
(Under "Known Problems in the Current Net Release".)

Cheers,
David


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