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Date: Wed, 16 Aug 2006 06:53:15 -0600
From: Eric Blake <ebb9 AT byu DOT net>
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To: cygwin AT cygwin DOT com, avi DOT cohenstuart AT ssaglobal DOT com
Subject: Re: openmotif, .rdata, shared libs and runtime linking/loading problem
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According to Avi Cohen Stuart on 8/15/2006 2:34 PM:
> Hi,
> 
> Please let me know if this is the correct newsgroup.

Actually, it is officially a mailing list (in spite of the fact that there
are some newsgroup frontends that people have created on the web).

> 
> When using windbg it reports a access violation here, apperantly during the
> resolving of shared libaries.

The cygwin and libtool archives document an issue where exporting a
library variable can cause problems, because initializing a const pointer
variable with its address will cause the const variable to live .rodata
but need a dynamic adjustment when the library is loaded; hence a SIGSEGV.
 I'm not fully sure of the details (so I hope I described the windows .dll
limitation correctly), but it sounds like you may have run into this
issue.  Perhaps you can find the place that takes the address of a library
variable and make that pointer non-const (so it won't be in .rodata).  A
more generic solution is to NEVER export variables in libraries, only
accessor functions.

- --
Life is short - so eat dessert first!

Eric Blake             ebb9 AT byu DOT net
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