X-Recipient: archive-cygwin AT delorie DOT com
X-SWARE-Spam-Status: No, hits=-0.8 required=5.0	tests=BAYES_20,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,RCVD_IN_DNSWL_LOW,RFC_ABUSE_POST,T_TO_NO_BRKTS_FREEMAIL
X-Spam-Check-By: sourceware.org
MIME-Version: 1.0
Date: Sun, 5 Dec 2010 13:58:27 +0000
Message-ID: <AANLkTik9fyXfLkm_vf-cZkjPovRAqnYtuVRKjv=soHpX@mail.gmail.com>
Subject: mrtd and duplicate header file loads
From: bill stoddart <w DOT j DOT stoddart AT googlemail DOT com>
To: cygwin AT cygwin DOT com
Content-Type: text/plain; charset=ISO-8859-1
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

Problem. When compiling using gcc and the -mrtd switch, two versions of any
included header library file may be loaded, and this generally results
in type errors.

This error was reported in a more specific form by Angel Robert Lynas
back in 2007,
though he only refers to time.h.

Here is an example program, called c1.c say


#include <signal.h>

main() { }


When compiled with gcc -mrtd c1.c the start of the error reports is

In file included from /usr/include/signal.h:5,
                 from c1.c:1:
/usr/include/sys/signal.h:171: error: conflicting types for 'sigwaitinfo'
/usr/include/cygwin/signal.h:265: error: previous declaration of
'sigwaitinfo' was here


So it looks like /usr/include/sys/signal.h has been erroneoulsy
included as well as
/usr/include/cygwin/signal.h

The problem, though present since approx 2007,  is absent from earlier
versions of Cygwin,
 e.g. 1.5.18, July 2005.

Kind Regards

   Bill Stoddart  w dot j dot stoddart at gmail dot com

PS to give some context, this problem has blocked us from porting a
virtual machine research project to
Cygwin, whioch we would still very much like to do. We will take the
__STDCALL route if it cannot be
fixed, but we do love the -mrtd switch.

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