From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D8FAFC4727F for ; Fri, 25 Sep 2020 17:46:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 73A67221EC for ; Fri, 25 Sep 2020 17:46:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="gRjk+y/M" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729660AbgIYRqI (ORCPT ); Fri, 25 Sep 2020 13:46:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56256 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728527AbgIYRqI (ORCPT ); Fri, 25 Sep 2020 13:46:08 -0400 Received: from mail-wr1-x444.google.com (mail-wr1-x444.google.com [IPv6:2a00:1450:4864:20::444]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AF355C0613CE; Fri, 25 Sep 2020 10:46:07 -0700 (PDT) Received: by mail-wr1-x444.google.com with SMTP id z4so4579726wrr.4; Fri, 25 Sep 2020 10:46:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=DasmCBY/wQlr/0J2E3YdX27/0Xwh8coAPdNm+mY0gxo=; b=gRjk+y/MXB5zoiWXwk0JODeINZZzLf91SeuV/00YvCR2aPwQBiG2V/iv6aPAFcjSU0 zlpwzu5+UQwDHe3cT5CZ/cfFGg6w/xYrwHxj+nv6RiVdVpg9FjjR4NmJ9ZbjvkE7wQ6I T7W5hcwC8EWNoHGFaI2O7QzhxBu4FXdBrQrtAldpewD2MBQE+4VY9SAcKXQHXmhV1r93 d+HRYPOUTr7ig84CKLQlcUvuuyRWw14laA/ANyF7g/wWgcV4GbLB6mhNTd4fzxxCf/fX 7RtRejVafnL1zojD8viZRY4PN6kXfpunXKxbG2kqI+7edOdal8s5LqdIRpbwAwLXzdw0 1bSg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=DasmCBY/wQlr/0J2E3YdX27/0Xwh8coAPdNm+mY0gxo=; b=H/JJut2hjj8JL3PC74uNWuzm4L6/TPmC6WlrTNA7dCOZolrAzGPWvnz9a2A1ZryxK4 IOPm6aZYnh9OcdxV31S9tIi9Zk5NFXGptLdbKQyFjYaN1wnwraR1Eru3ha4S/hqfQQdd 7XAVM0m6aFwvrRD9MQDgGOyS6Owa/PQ39a31nplFQmvQdIOwvEOXKMXmLuynA4NYGfWD LvTXdjwJBdut8sXeFwS9Y1XnVC8DWO6VnkoSMYIT3WQ2iVjkB6AbJaiWHTYStscSrW7H hkP04xQpO6FUDCyfp0gyOZ7Sw7x00EpxvRQMIQJe39yQo6kHYZzgBxKEb/GMXiHzufvx L05w== X-Gm-Message-State: AOAM532HOBoB2jzc5kJxyPd3EpN7eqCqx2NH8oRU8cUh3rvQiAow7lEo y4pUFasCjnVNCdy0PUeGRBQlS0KktYJR5Q== X-Google-Smtp-Source: ABdhPJyh3QXyThiBe9yeSw9Yh8lRFZO7Hu9wXz+dDehB5AoOPFjOAG3ht3gxa02t+7zFBo6lMXuHkw== X-Received: by 2002:a5d:4486:: with SMTP id j6mr5520651wrq.278.1601055966425; Fri, 25 Sep 2020 10:46:06 -0700 (PDT) Received: from [192.168.1.143] ([170.253.60.68]) by smtp.gmail.com with ESMTPSA id w21sm3880599wmk.34.2020.09.25.10.46.05 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 25 Sep 2020 10:46:05 -0700 (PDT) Subject: Re: [PATCH v2] : Add nitems() and snitems() macros To: Jonathan Wakely Cc: fweimer@redhat.com, linux-man@vger.kernel.org, libc-alpha@sourceware.org, gcc@gcc.gnu.org, rusty@rustcorp.com.au, linux-kernel@vger.kernel.org, libstdc++@gcc.gnu.org, libc-coord@lists.openwall.com, enh@google.com References: <20200922145844.31867-1-colomar.6.4.3@gmail.com> <20200925132000.235033-1-colomar.6.4.3@gmail.com> <20200925144822.GM6061@redhat.com> <22c110fe-4c92-e5e6-dc35-dbf00a97cfa2@gmail.com> <20200925174252.GO6061@redhat.com> From: Alejandro Colomar Message-ID: Date: Fri, 25 Sep 2020 19:46:04 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.12.0 MIME-Version: 1.0 In-Reply-To: <20200925174252.GO6061@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020-09-25 19:39, Jonathan Wakely wrote: > Yes, I'm aware of all the rationale. I already said that it makes > sense in C++ where you have generic code. I am not convinced that it's > necessary to add to when all it does is a cast from > size_t to ptrdiff_t. > While I would prefer a signed version, I could live with only 'nitems()'. Having all the __must_be_array thing is the most important part. On 2020-09-25 19:42, Jonathan Wakely wrote: > On 25/09/20 18:30 +0200, Alejandro Colomar via Libstdc++ wrote: >> I have a similar number of ARRAY_SIZE() and ARRAY_SSIZE(). >> I could have '#define snitems(arr) ((ptrdiff_t)nitems(arr))' in my >> projects, >> but is it really necessary? > > The barrier for adding something to glibc headers should be a LOT > higher than "I could [do it in my own code], but is it really > necessary?" > >> Did I convince you? :-) > > No. > > Well, you convinced me :) I'll rewrite the patch, and the problem about will vanish. Cheers, Alex