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Date: Sun, 29 Aug 2010 21:52:15 -0400
From: "Larry Hall \(Cygwin\)" <reply-to-list-only-lh AT cygwin DOT com>
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To: cygwin AT cygwin DOT com
Subject: Re: Linking shared libraries problem
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On 8/29/2010 7:08 PM, Tomás Staig wrote:
> Hi,
> I have been trying to port some software from Linux (Scientific Linux/RedHat)
> to windows using Cygwin. I have been able to port most of it with little
> changes but I encountered a problem when linking shared libraries. It seems
> that the chain of dependencies is not included when linking. Furthermore, ldd
> does not show the dependency libraries as in Linux. I have tried both using
> the import libraries (%.dll.a) and linking the dll files (%.dll) directly.
>
> I have arranged a small example program that reproduces this effect.
> Used Ubuntu 8.04 to and "CYGWIN_NT-5.1" version "1.7.6(0.230/5/3) 2010-08-16
> 16:06" on top of a 32-bits Windows XP Machine to test the above examples.

<snip>

> As you can see, there is no reference to liby.dll. I could add the library
> (-ly) directly to the compiling line of main and it works, but the truth is
> that it would not be a good approach, since in the software I'm trying to
> port, there are several dependent modules, so the last ones would have an
> incredibly large list of dependencies.
>
> So, am I doing something wrong? Is there any way to add the dependency to be
> shown with ldd or any workaround(maybe a linker flag or something) to make
> the above example work?

The Windows loader requires full resolution at link time.  You need to list
at least the import libraries for all dependencies if you want the link
to succeed.  Sorry, that's just the way Windows works.

-- 
Larry Hall                              http://www.rfk.com
RFK Partners, Inc.                      (508) 893-9779 - RFK Office
216 Dalton Rd.                          (508) 893-9889 - FAX
Holliston, MA 01746

_____________________________________________________________________

A: Yes.
> Q: Are you sure?
>> A: Because it reverses the logical flow of conversation.
>>> Q: Why is top posting annoying in email?

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