Mailing-List: contact cygwin-help AT sourceware DOT cygnus DOT com; run by ezmlm
Sender: cygwin-owner AT sourceware DOT cygnus DOT com
Delivered-To: mailing list cygwin AT sourceware DOT cygnus DOT com
Message-Id: <199903310224.UAA25643@modi.xraylith.wisc.edu>
X-Authentication-Warning: modi.xraylith.wisc.edu: localhost.xraylith.wisc.edu [127.0.0.1] didn't use HELO protocol
To: JSONCRAIG AT aol DOT com
cc: cygwin AT sourceware DOT cygnus DOT com
Subject: Re: Relocatable DLLs 
In-reply-to: Your message of "Tue, 30 Mar 1999 20:09:01 EST."
             <1ce25344 DOT 370175ad AT aol DOT com> 
Date: Tue, 30 Mar 1999 20:24:32 -0600
From: Mumit Khan <khan AT xraylith DOT wisc DOT EDU>

JSONCRAIG AT aol DOT com writes:
> I searched for this but couldn't find anything on it.
> 
> When I try to link my dll that has a function that uses iostream (I'm linking
> -lstdc++ with it) I get a bunch of undefined references like "undefined
> refernece to isspace".  I don't know what I'm doing wrong...heres the ld
> command
> 
> ld -s --base-file foo.base --dll -o foo.dll foo.o -lstdc++ -e _dllEntry AT 12
> 
> Can anyone help?

First of all, I suggest looking at the README file and the examples that
come with dllhelpers package. It would've answered your question right
away. See http://www.xraylith.wisc.edu/~khan/software/gnu-win32/ for more
info.

If you insist on using "ld" to link, then you must know all the other
libraries that are needed, as well as other options that language drivers,
such as gcc and c++, pass on to ld. In this particular case, you're
missing -lcygwin.

I suggest you use c++ to do the job. To make your life easier, just use
dllwrap and be done with it.

  $ dllwrap -o foo.dll --driver-name=c++ --entry _dllEntry AT 12 foo.o

or,

  $ dllwrap -o foo.dll --entry _dllEntry AT 12 foo.o -lstdc++

Will build a relocatable DLL (ie., run all 5 passes) for you. Since you're
not specifying a DEF file, I'm assuming that you've used dllexport
attribute in all places necessary. For C++ code, you almost always have to
use --export-all to export everything needed (some are due to bugs and
misfeatures in GCC's dllexport attribute).

  $ dllwrap -o foo.dll --export-all --implib=libfoo.a \
    --entry _dllEntry AT 12 foo.o -lstdc++

Regards,
Mumit


--
Want to unsubscribe from this list?
Send a message to cygwin-unsubscribe AT sourceware DOT cygnus DOT com