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From: "Avi Cohen Stuart" <avics AT xs4all DOT nl>
Subject:  Re: openmotif, .rdata, shared libs and runtime linking/loading problem
Date:  Wed, 16 Aug 2006 23:51:44 +0200
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References:  <ebtb3s$l2a$1 AT sea DOT gmane DOT org> <44E3153B DOT 5080304 AT byu DOT net>
Reply-To: "Avi Cohen Stuart" <avi DOT cohenstuart AT ssaglobal DOT com>
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Hi Eric,

>> 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).

I'm indeed using the gmane.os.cygwin as a frontend...

>> 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.

This might indeed be the problem where the Xm library is trying to use 
XtStrings from the Xt library.
I'll try a recompile tomorrow where these const strings of Xt are not used 
in Xm.

Avi.




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