Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D224DC433F5 for ; Thu, 2 Dec 2021 20:48:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349025AbhLBUwO (ORCPT ); Thu, 2 Dec 2021 15:52:14 -0500 Received: from out4-smtp.messagingengine.com ([66.111.4.28]:48249 "EHLO out4-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238643AbhLBUwN (ORCPT ); Thu, 2 Dec 2021 15:52:13 -0500 Received: from compute5.internal (compute5.nyi.internal [10.202.2.45]) by mailout.nyi.internal (Postfix) with ESMTP id 844045C01E1; Thu, 2 Dec 2021 15:48:49 -0500 (EST) Received: from imap45 ([10.202.2.95]) by compute5.internal (MEProxy); Thu, 02 Dec 2021 15:48:49 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=owlfolio.org; h= mime-version:message-id:in-reply-to:references:date:from:to:cc :subject:content-type; s=fm2; bh=V+oY0lvpRQ6EWyHSpKOwdyQZHvigeH/ DqFU+688VfMY=; b=nb/nkksHB3a3v4m7IZp4fqN9v2xH5hSYXlFYTlHB+UWrVyH zTDvXiG5u/13oPUWZiI6qmf0PYrvqXZEvdl2SqEr4Y6QawYYzmnseHuysVT/lFIq V8MNlx4x00WGzc5fNSo+1GgM1UOD3mwX1IZ4Vp/T5pQc7VzQb6gZ6u0KrdEmDK9N xbsHXGFoSCie3plt1DgqtjMNV06JXlML19Zz0H/vf5Bq/klVz+0M1ohEHRNYDPeo IL7Cg8Y5P3pHdGfvgdXBSkSfMVKquO9L+7h7bg4QA3Zrg76+DszVT13+n7r5KNlb iriUINGYx8Ze31uCpxdzOO2Gv0t1NknSTRbPfHA== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to:x-me-proxy :x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm1; bh=V+oY0l vpRQ6EWyHSpKOwdyQZHvigeH/DqFU+688VfMY=; b=NQm5/SdfzT+EZ/AqkRR47a QX4yiM4sJjwLX4m6PvlVoMNjX+Uns4jeRpZTM7mMBWBlh3l8ufG/VWwDtu2brul0 bRGYNECR1HwGvbO5xZYs5c8IJ5eyUpagJdfeekv2EHQbHJ1uDSHRjFbaXx/dDfwt TrV6iAZ8rAPqjZv3bVNtCx2Y9+EDrV11Ss/gUVNwcT5D6gla9+H9PwBjnLpL4vc6 aljzCB68dMyH3Hg1PxjcBiJ85Eu61QapWuAGoJRsT1MRbqrh6ogBoZt7d6C6bmPS /VXkBMhkDj89rsmYNou+/aiC93ISbgkOKnA1tsiLHlqP3HuH8g2CZKkomwPlG1Qw == X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvuddrieehgddugeduucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne cujfgurhepofgfggfkjghffffhvffutgesthdtredtreertdenucfhrhhomhepfdgkrggt khcuhggvihhnsggvrhhgfdcuoeiirggtkhesohiflhhfohhlihhordhorhhgqeenucggtf frrghtthgvrhhnpefhuefhveeuffetfffgjeetgfekkeehfedtfeelgfehffffveehkeel fefgheffudenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhroh hmpeiirggtkhesohiflhhfohhlihhordhorhhg X-ME-Proxy: Received: by mailuser.nyi.internal (Postfix, from userid 501) id 11E5C24A0077; Thu, 2 Dec 2021 15:48:48 -0500 (EST) X-Mailer: MessagingEngine.com Webmail Interface User-Agent: Cyrus-JMAP/3.5.0-alpha0-4458-g51a91c06b2-fm-20211130.004-g51a91c06 Mime-Version: 1.0 Message-Id: <1e3867cd-2c8b-4fe1-93a6-c6ae34120f6b@www.fastmail.com> In-Reply-To: <913509.1638457313@warthog.procyon.org.uk> References: <1618289.1637686052@warthog.procyon.org.uk> <913509.1638457313@warthog.procyon.org.uk> Date: Thu, 02 Dec 2021 15:48:21 -0500 From: "Zack Weinberg" To: "David Howells" Cc: "linux-arch@vger.kernel.org" , "Florian Weimer" , "linux-api@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "David Laight" , "ltp@lists.linux.it" Subject: Re: [PATCH] uapi: Make __{u,s}64 match {u,}int64_t in userspace Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Dec 2, 2021, at 10:01 AM, David Howells via Libc-alpha wrote: > Zack Weinberg wrote: >> I could be persuaded otherwise with an example of a program for which >> changing __s64 from 'long long' to 'long' would break *binary* backward >> compatibility, or similarly for __u64. > > C++ could break. That's too hypothetical to be actionable. I would like to see a _specific program_, and I would like it to be one that already exists in the world and was not written as a test case for this hypothetical ABI break. zw