From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-4.1 required=3.0 tests=AWL,BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,RCVD_IN_DNSWL_HI,RP_MATCHES_RCVD shortcircuit=no autolearn=ham autolearn_force=no version=3.4.0 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id E4B52201B0 for ; Tue, 28 Feb 2017 20:12:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751435AbdB1UM3 (ORCPT ); Tue, 28 Feb 2017 15:12:29 -0500 Received: from cloud.peff.net ([104.130.231.41]:35900 "EHLO cloud.peff.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750957AbdB1UM0 (ORCPT ); Tue, 28 Feb 2017 15:12:26 -0500 Received: (qmail 19223 invoked by uid 109); 28 Feb 2017 20:04:26 -0000 Received: from Unknown (HELO peff.net) (10.0.1.2) by cloud.peff.net (qpsmtpd/0.84) with SMTP; Tue, 28 Feb 2017 20:04:26 +0000 Received: (qmail 29580 invoked by uid 111); 28 Feb 2017 20:04:31 -0000 Received: from sigill.intra.peff.net (HELO sigill.intra.peff.net) (10.0.0.7) by peff.net (qpsmtpd/0.84) with SMTP; Tue, 28 Feb 2017 15:04:31 -0500 Received: by sigill.intra.peff.net (sSMTP sendmail emulation); Tue, 28 Feb 2017 15:04:23 -0500 Date: Tue, 28 Feb 2017 15:04:23 -0500 From: Jeff King To: Junio C Hamano Cc: =?utf-8?B?UmVuw6k=?= Scharfe , Johannes Schindelin , git@vger.kernel.org Subject: Re: [PATCH 0/6] Use time_t Message-ID: <20170228200423.33dghyephxsmxrx6@sigill.intra.peff.net> References: <20170228142802.hu5esthnqdsgc2po@sigill.intra.peff.net> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Tue, Feb 28, 2017 at 10:55:49AM -0800, Junio C Hamano wrote: > > Glibc will get a way to enable 64-bit time_t on 32-bit platforms > > eventually > > (https://sourceware.org/glibc/wiki/Y2038ProofnessDesign). Can > > platforms that won't provide a 64-bit time_t by 2038 be actually used > > at that point? How would we get time information on them? How would > > a custom timestamp_t help us? > > That's a sensible "wait, let's step back a bit". I take it that you > are saying "time_t is just fine", and I am inclined to agree. > > Right now, they may be able to have future timestamps ranging to > year 2100 and switching to time_t would limit their ability to > express future time to 2038 but they would be able to express > timestamp in the past to cover most of 20th century. Given that > these 32-bit time_t software platforms will die off before year 2038 > (either by underlying hardware getting obsolete, or software updated > to handle 64-bit time_t), the (temporary) loss of 2038-2100 range > would not be too big a deal to warrant additional complexity. For what it's worth, I'm on board with just using time_t if it reduces the overall complexity. I agree that the "loss" of far-future timestamp handling is unlikely to matter between now and 2038, and those systems will have to figure out their time_t problems by then. By actually using time_t we get to piggy-back on their solution. -Peff