X-Recipient:	archive-cygwin AT delorie DOT com
DomainKey-Signature:	a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id
	:list-unsubscribe:list-subscribe:list-archive:list-post
	:list-help:sender:from:subject:to:message-id:date:mime-version
	:content-type:content-transfer-encoding; q=dns; s=default; b=u/s
	MvUDQTKjF/lBQ1yW0MPywuHPxz2lZdAxGL5o9kBiQer9D3paTYen3FrHkfkMY8TU
	v22GTR2xGDqL/9lz2dCNQqsjFvBI9ItQfN0hQVw/uzU44ZPGNNuKUK3mV0BZ8uDe
	lEgbkSQS7PsAOwxyw9pj/8aL1r0WQGzlNQyK+JMg=
DKIM-Signature:	v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id
	:list-unsubscribe:list-subscribe:list-archive:list-post
	:list-help:sender:from:subject:to:message-id:date:mime-version
	:content-type:content-transfer-encoding; s=default; bh=NylNmvoYB
	YMlZe4nOO+gPb8LWtw=; b=FzKdP7+yu0+iqYHWC42dwHSvYkT3clzrSC8MYJ8UY
	v0py8+j92UeNmd4FNTvbz779Y6n8FreiHyZDG0Arfg889KGKALAkdWLMEvrOK8Is
	SHatQFSFHmL20TOKWpJ5awgJNlOBStdmW7dQB96AXKIstqdnXXD0MW3wn3EhuPOX
	+0=
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
Authentication-Results:	sourceware.org; auth=none
X-Virus-Found:	No
X-Spam-SWARE-Status:	No, score=-2.4 required=5.0 tests=AWL,BAYES_00,FREEMAIL_FROM,RCVD_IN_DNSWL_LOW,SPF_PASS autolearn=ham version=3.3.2 spammy=identified, vertical
X-HELO:	mail-wm0-f45.google.com
X-Google-DKIM-Signature:	v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:subject:to:message-id:date:user-agent :mime-version:content-transfer-encoding; bh=qY1rkZ7gngtmWlHoXvAZWcCw1ORvWGaxtUIjzvacFvk=; b=Ew66d+UwqK2/8X7VM4p2yi2CH9vYk7k/uthxY26rBxZqhqLaQdlmXO0zSWg1fec8cW +3ZOAAQRUb0S1QLWZ/TUE6ipL3rwQwGD0Yl5FuIgH6k6iFEpSAlrWukURG9Lwl4XxA+3 PceHAVAqZ+9ndNCH0lnxfkWqtM35d0NdWRtUDfOLVt7qnqxAl7X/TsR1GJyvXdA7vbGh z6bXMR3lhSVSBpAaASCJIFQ2Q5Av5izGXKS52kVxt7G5eMFFQBGENexnWsK912ydaa/+ BeLjmN2QIjcT0rVapPxXEYBY5Tkg3P+y0xsgP5AxcL6mNqsxeq6q3+7CnEV9KmzzXnqu eF4g==
X-Gm-Message-State:	AD7BkJKlVQxUNWVlokJnrneRVhGNDuu3J4cCup/Dxs7MvW3J6AitjVLCE1df+k/7pp783g==
X-Received:	by 10.28.99.6 with SMTP id x6mr8451437wmb.46.1458467865791; Sun, 20 Mar 2016 02:57:45 -0700 (PDT)
From:	Marco Atzeri <marco DOT atzeri AT gmail DOT com>
Subject:	X widget question
To:	"cygwin AT cygwin DOT com" <cygwin AT cygwin DOT com>
Message-ID:	<56EE7412.8080708@gmail.com>
Date:	Sun, 20 Mar 2016 10:57:38 +0100
User-Agent:	Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.7.0
MIME-Version:	1.0
X-IsSubscribed:	yes

I have finally identified where ncview was
segfaulting on X86_64

The solution was to reverse the order of destruction
for a chain of widgets

         i=0;
-       while( (w = *(diminfo_row_widget + i++)) != NULL )
-               XtDestroyWidget( w );
+       while( (w = *(diminfo_row_widget + i)) != NULL )
+               i++;
+       while( i>0 ) {
+               i--;
+               XtDestroyWidget( *(diminfo_row_widget + i ));
+       }
  }

that were connected by a vertical constraints:

     *(diminfo_row_widget+ll) = XtVaCreateManagedWidget(
            widget_name,
            boxWidgetClass,
            commandcanvas_widget,
            XtNorientation, XtorientHorizontal,
            XtNfromVert, *(diminfo_row_widget + (ll-1)),
            XtNheight, bb_height,
            XtNwidth,  bb_width,
            NULL);

The segfault was inside Xlib when managing the constraints.

As the segfault did not happened on i686, is it possible
that is a race inside Xlib  ?
I have not found in the X Documentation nothing about
requested order of widget destruction in this case.

Thanks in advance
Marco

--
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

- Raw text -