X-Spam-Check-By: sourceware.org
Message-ID: <46728D53.972514F3@dessent.net>
Date: Fri, 15 Jun 2007 06:00:04 -0700
From: Brian Dessent <brian AT dessent DOT net>
X-Mailer: Mozilla 4.79 [en] (Windows NT 5.0; U)
MIME-Version: 1.0
To: cygwin AT cygwin DOT com
Subject: Re: gcc with glib
References: <467155CA DOT 51269500 AT dessent DOT net> <BAF83494CE653943A97B9F755016A0660513602F AT ftrdmel1 DOT rd DOT francetelecom DOT fr>
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
X-IsSubscribed: yes
Reply-To: cygwin AT cygwin DOT com
Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Id: <cygwin.cygwin.com>
List-Subscribe: <mailto:cygwin-subscribe AT cygwin DOT com>
List-Archive: <http://sourceware.org/ml/cygwin/>
List-Post: <mailto:cygwin AT cygwin DOT com>
List-Help: <mailto:cygwin-help AT cygwin DOT com>, <http://sourceware.org/ml/#faqs>
Sender: cygwin-owner AT cygwin DOT com
Mail-Followup-To: cygwin AT cygwin DOT com
Delivered-To: mailing list cygwin AT cygwin DOT com

PRIEUR Christophe RD-TECH-ISS wrote:

> Okay!  You're right, it works.  I guess some versions of gcc are a bit
> more open-minded on this issue (trying to save my self-esteem of old C
> programmer).

It has nothing to do with gcc.  It's a property of the linker (ld) which
is a separate external program, and this behavior is as old as unix,
i.e. it's been this way forever.

What you might have been trying to say is that on some ELF systems such
as Linux or Solaris the order doesn't matter, but this is true only when
linking with shared libraries.  The order must still be correct even on
these systems when linking with static archives.  Try the following on
Linux:

$ echo "int foo (void) { return 42; }" > foo.c && \
cc -c foo.c -o foo.o && \
ar rcs libfoo.a foo.o && \
echo 'extern int foo (void);
int main (int c, char **v) { return foo (); }' > main.c && \
cc -c main.c -o main.o && \
cc -L. -lfoo main.o -o main
main.o: In function `main':
main.c:(.text+0x1d): undefined reference to `foo'
collect2: ld returned 1 exit status

$ cc main.o -L. -lfoo -o main && ./main ; echo $?
42

Brian

--
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple
Problem reports:       http://cygwin.com/problems.html
Documentation:         http://cygwin.com/docs.html
FAQ:                   http://cygwin.com/faq/