From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on yquem.inria.fr X-Spam-Level: X-Spam-Status: No, score=0.4 required=5.0 tests=AWL,DNS_FROM_RFC_ABUSE autolearn=disabled version=3.1.3 X-Original-To: caml-list@yquem.inria.fr Delivered-To: caml-list@yquem.inria.fr Received: from mail2-relais-roc.national.inria.fr (mail2-relais-roc.national.inria.fr [192.134.164.83]) by yquem.inria.fr (Postfix) with ESMTP id 933DFBC6C for ; Fri, 18 Jan 2008 10:12:24 +0100 (CET) X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: Ao8CAGr8j0eCNhAB/2dsb2JhbACtaw X-IronPort-AV: E=Sophos;i="4.25,215,1199660400"; d="scan'208";a="6272886" Received: from kurims.kurims.kyoto-u.ac.jp ([130.54.16.1]) by mail2-smtp-roc.national.inria.fr with ESMTP; 18 Jan 2008 10:12:23 +0100 Received: from localhost (orion [130.54.16.5]) by kurims.kurims.kyoto-u.ac.jp (8.13.8/8.13.8) with ESMTP id m0I9CDAR001555; Fri, 18 Jan 2008 18:12:13 +0900 (JST) Date: Fri, 18 Jan 2008 18:12:06 +0900 (JST) Message-Id: <20080118.181206.85503086.garrigue@math.nagoya-u.ac.jp> To: till.varoquaux@gmail.com Cc: caml-list@yquem.inria.fr Subject: Re: [Caml-list] Strange performances From: Jacques Garrigue In-Reply-To: <9d3ec8300801172339j38bf734dm5b84f951a4342188@mail.gmail.com> References: <1200619933.6383.47.camel@benjamin-laptop> <20080118.111503.185813743.garrigue@math.nagoya-u.ac.jp> <9d3ec8300801172339j38bf734dm5b84f951a4342188@mail.gmail.com> X-Mailer: Mew version 4.2 on Emacs 22.1 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Spam: no; 0.00; segfaults:01 segfaults:01 segfault:01 ocaml's:01 out-of-bound:01 wrote:01 stack:01 stack:01 caml-list:01 unsafe:01 behaviour:01 native:03 garrigue:03 garrigue:03 seems:03 From: "Till Varoquaux" > On Jan 18, 2008 2:15 AM, Jacques Garrigue wrote: > ... > > By the way, on my machine your version doesn't even work in native > > code, I only get segfaults. This is allowed behaviour for > > out-of-bounds access. > > Could you please clarify? This seems a little scary to me, I thought > segfaults where acceptable only when you used unsafe features (or ran > out of stack). This is why I sent an erratum. The cause for the segfault was not the array access, but the stack overflow, which occured due to ocaml's peculiar evaluation order. Still, I maintain that intentionally raising and catching out-of-bound accesses is not good programming style... Jacques Garrigue