From help-octave-request at bevo dot che dot wisc dot edu Tue Feb  5 17:14:20 2002
Subject: Re: Windows and dynamically linked files
From: Roberto Hernandez <robher at adinet dot com dot uy>
To: Douglas Eck <doug at idsia dot ch>
CC: help-octave at bevo dot che dot wisc dot edu
Date: Tue, 05 Feb 2002 20:14:31 -0300

Douglas Eck wrote:

> [cc replies  to doug at idsia dot ch please]
> 
> Hello all,
> 
> I downloaded 2.1.35 and a fresh install of cygwin. I did a
> ./configure and a make and everything compiled. However,
> if I cd into SRC/examples and try to build an oct file
> I get a slew of undefined references. I don't have a way to get
> the output from my laptop onto the machine I"m typing from.
> But there are many failed references, such as to Array<octave_value>::
> ~Array(void) which I suppose is in liboctave.a
> 
> I've ensured that liboctave.a, libcruft.a and liboctinterp.a are all
> visible but the linker doesn't seem to link to them. I read that perhaps
> I need
> to do ./configure --enable-shared but then the build fails
> with undefined references in some of the fortran libs. For example
> [from the output from make]
> c++ -shared -o libcruft.so.2.1.35  [lots of obj files]
> yields hundreds of failed references to, eg,  s_copy, s_wsfi, do_fio
> e_wsfi


You do need to include "--enable-shared". I can confirm that much.

The problem is that shared library support is not fully developed in 
Cygwin. The following text comes from the Cygwin-Announce mailing list 
(http://cygwin.com/ml/cygwin-announce/2002/msg00042.html):

-----------------------------
1) libtool (along with autoconf and automake) are really only for
developer use.  If you don't already have a good understanding of
how to use the tools -- and experience using them on a "normal"
unix platform -- then you probably DON'T want to "learn" with this
port.  The combination of
    a) the brain dead DLL format (compared to elf shared libs)
    b) still evolving shared lib support in the binutils/gcc/cygwin
    c) the VERY beta status of libtool-devel
    d) the wacky -stable/-devel/wrapper structure we are forced to
       use means that cygwin is NOT a good platform to "learn how to
       use the autotools".

PLEASE do not ask for tutorials on automake/autoconf/libtool use
on the cygwin mailing list -- you will either be ignored, or mocked.
-----------------------------

 
> Perhaps I need to build a shared version of libstdc++?
> I think I'm missing something obvious here... any suggestions?

I'm also interested in using dynamically linked functions in Octave 
under Windows. Unfortunately, I'm far from "developer" status. I might 
devote some time in the near future to try to get that running, but I'm 
not sure what the results will be.

If you make any progress in that area, please report it to the list, I'm 
sure there's many more who could benefit.

Regards,

Roberto.



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