From mboxrd@z Thu Jan 1 00:00:00 1970 From: Linus Torvalds Subject: Re: heads-up: git-index-pack in "next" is broken Date: Tue, 17 Oct 2006 14:46:04 -0700 (PDT) Message-ID: References: <7vy7rfsfqa.fsf@assigned-by-dhcp.cox.net> <7vslhnj58e.fsf@assigned-by-dhcp.cox.net> <7vbqoake1v.fsf@assigned-by-dhcp.cox.net> <20061017233630.72a0aae5.vsu@altlinux.ru> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Cc: Sergey Vlasov , Junio C Hamano , git@vger.kernel.org X-From: git-owner@vger.kernel.org Tue Oct 17 23:47:21 2006 Return-path: Envelope-to: gcvg-git@gmane.org Received: from vger.kernel.org ([209.132.176.167]) by ciao.gmane.org with esmtp (Exim 4.43) id 1GZwlP-0002mU-Lv for gcvg-git@gmane.org; Tue, 17 Oct 2006 23:46:20 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750911AbWJQVqQ (ORCPT ); Tue, 17 Oct 2006 17:46:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750900AbWJQVqQ (ORCPT ); Tue, 17 Oct 2006 17:46:16 -0400 Received: from smtp.osdl.org ([65.172.181.4]:62134 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1750898AbWJQVqP (ORCPT ); Tue, 17 Oct 2006 17:46:15 -0400 Received: from shell0.pdx.osdl.net (fw.osdl.org [65.172.181.6]) by smtp.osdl.org (8.12.8/8.12.8) with ESMTP id k9HLk5aX003084 (version=TLSv1/SSLv3 cipher=EDH-RSA-DES-CBC3-SHA bits=168 verify=NO); Tue, 17 Oct 2006 14:46:06 -0700 Received: from localhost (shell0.pdx.osdl.net [10.9.0.31]) by shell0.pdx.osdl.net (8.13.1/8.11.6) with ESMTP id k9HLk4xQ006915; Tue, 17 Oct 2006 14:46:04 -0700 To: Nicolas Pitre In-Reply-To: X-Spam-Status: No, hits=-0.474 required=5 tests=AWL X-Spam-Checker-Version: SpamAssassin 2.63-osdl_revision__1.95__ X-MIMEDefang-Filter: osdl$Revision: 1.155 $ X-Scanned-By: MIMEDefang 2.36 Sender: git-owner@vger.kernel.org Precedence: bulk X-Mailing-List: git@vger.kernel.org Archived-At: On Tue, 17 Oct 2006, Nicolas Pitre wrote: > > Because offsets into packs are expressed as unsigned long everywhere > else (except in the current pack index on-disk format). Until your work, that "unsigned long" was totally just an internal thing that didn't actually bleed into anything else. > > For some structure like this, it sounds positively wrong. Pack-files > > should be architecture-neutral, which means that they shouldn't depend on > > word-size, and they should be in some neutral byte-order. > > But they do. Please consider this code: Right. The pack-file itself. But the code that actually _generates_ it mixes things in alarming ways. > > In contrast, the new union introduced in "next" is just horrid. There's > > not even any way to know which member to use, except apparently that it > > expects that a SHA1 is never zero in the last 12 bytes. Which is probably > > true, but still - that's some ugly stuff. > > This union should be looked at just like a sortable hash pointing to a > base object so that deltas with the same base object can be sorted > together. .. and it sorts _differently_ on a big-endian vs little-endian thing, doesn't it? So now the sort order depends on endianness and/or wordsize. That just sounds really really wrong. Linus