From mboxrd@z Thu Jan 1 00:00:00 1970 Path: main.gmane.org!not-for-mail From: Rob Browning Newsgroups: gmane.lisp.guile.devel Subject: Everyone working on the C side might want to read this article... Date: Thu, 17 Apr 2003 15:00:22 -0500 Sender: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Message-ID: <873ckgevxl.fsf@raven.i.defaultvalue.org> NNTP-Posting-Host: main.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: main.gmane.org 1050610216 20644 80.91.224.249 (17 Apr 2003 20:10:16 GMT) X-Complaints-To: usenet@main.gmane.org NNTP-Posting-Date: Thu, 17 Apr 2003 20:10:16 +0000 (UTC) Original-X-From: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Thu Apr 17 22:10:07 2003 Return-path: Original-Received: from monty-python.gnu.org ([199.232.76.173]) by main.gmane.org with esmtp (Exim 3.35 #1 (Debian)) id 196Fhg-0005Li-00 for ; Thu, 17 Apr 2003 22:09:52 +0200 Original-Received: from localhost ([127.0.0.1] helo=monty-python.gnu.org) by monty-python.gnu.org with esmtp (Exim 4.10.13) id 196FdD-00046r-01 for guile-devel@m.gmane.org; Thu, 17 Apr 2003 16:05:15 -0400 Original-Received: from list by monty-python.gnu.org with tmda-scanned (Exim 4.10.13) id 196FYu-0002V3-00 for guile-devel@gnu.org; Thu, 17 Apr 2003 16:00:48 -0400 Original-Received: from mail by monty-python.gnu.org with spam-scanned (Exim 4.10.13) id 196FYl-0002Ei-00 for guile-devel@gnu.org; Thu, 17 Apr 2003 16:00:40 -0400 Original-Received: from dsl093-098-016.wdc1.dsl.speakeasy.net ([66.93.98.16] helo=defaultvalue.org) by monty-python.gnu.org with esmtp (Exim 4.10.13) id 196FYe-00021B-00 for guile-devel@gnu.org; Thu, 17 Apr 2003 16:00:33 -0400 Original-Received: from raven.i.defaultvalue.org (raven.i.defaultvalue.org [192.168.1.7]) by defaultvalue.org (Postfix) with ESMTP id 28A7613888 for ; Thu, 17 Apr 2003 15:00:22 -0500 (CDT) Original-Received: by raven.i.defaultvalue.org (Postfix, from userid 1000) id 133D021521B; Thu, 17 Apr 2003 15:00:22 -0500 (CDT) Original-To: guile-devel@gnu.org User-Agent: Gnus/5.090008 (Oort Gnus v0.08) Emacs/21.2 (i386-pc-linux-gnu) X-BeenThere: guile-devel@gnu.org X-Mailman-Version: 2.1b5 Precedence: list List-Id: Developers list for Guile, the GNU extensibility library List-Help: List-Post: List-Subscribe: , List-Archive: List-Unsubscribe: , Errors-To: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Xref: main.gmane.org gmane.lisp.guile.devel:2174 X-Report-Spam: http://spam.gmane.org/gmane.lisp.guile.devel:2174 The following article explains gcc changes that may be behind at least some of our recent set of bugs: http://www.ddj.com/documents/s=880/ddj0010d/0010d.htm You may not need to read it if you're already familiar with what the C standard says about type aliasing, or already know that (for example) according to the standard this code is illegal and the results are undefined: double d = 3.0; int* ip = (int*) &d; *ip = 7; or if you know that an optimizer is within its rights according to the standard to translate this:code: double d = 2.0; int *ip = (int*) &d; *ip = 3; d *= 2; into this code: double d = 2.0; int *ip = (int*) &d; d *= 2; *ip = 3; Thanks to Marius for tracking the pointer down. I'm not yet sure what this means for our code. -- Rob Browning rlb @defaultvalue.org, @linuxdevel.com, and @debian.org Previously @cs.utexas.edu GPG starting 2002-11-03 = 14DD 432F AE39 534D B592 F9A0 25C8 D377 8C7E 73A4 _______________________________________________ Guile-devel mailing list Guile-devel@gnu.org http://mail.gnu.org/mailman/listinfo/guile-devel