Problem porting linux shared library to windows using cygwin and libtool

[Thomas Leitner]

Hi!

I have been using libtool for one of my projects under linux and now I am in 
the progress of porting this project to windows using Cygwin.

Fortunately, all the configuration stuff worked fine, but when it came to the 
compilation part, some things went wrong.

I have native Windows DLLs and the approriate .def files which I converted to 
import libraries using dlltool. 

dlltool --def /cygdrive/c/MATLAB6p5/extern/include/libmat.def --dllname 
libmat.dll --output-lib libmat.a

The same for the other libraries.

Three C++ files are compiled and then linked together to create a shared 
library but that shared library depends on the former mentioned Windows DLLs. 
Every time libtool wants to link all compiled files together it gives the 
following warning:

*** Warning: linker path does not have real file for library -lmex.
*** I have the capability to make that library automatically link in when
*** you link to this library.  But I can only do this if you have a
*** shared version of the library, which you do not appear to have
*** because I did check the linker path looking for a file starting
*** with libmex and none of the candidates passed a file format test
*** using a file magic. Last file checked: /cygdrive/c/matlab6p5/bin/win32/libme
x.dll

The same warning comes for -lmat and -lmx (the shared library should link 
against the Matlab MEX interface).

After that libtool only creates a static version of the library. This would 
normally be okay but I cannot link to my library. I have some C++ files that 
use my library but when they should be created the compiler/linker only 
produces 'undefined reference to ...' errors.

The strange thing is that I can compile everything manually and link everything 
together without using libtool. This works fine.

So, to sum up:
* I have three files which should become one shared library referencing three 
other libraries for which I have created the import libs.
* I have some C++ source files which reference the created library and 
themselves should be come shared libraries.


I have searched on the Internet for information about this or similar problems 
but found nothing useful.


Thomas