From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from out4-smtp.messagingengine.com (out4-smtp.messagingengine.com [66.111.4.28]) by sourceware.org (Postfix) with ESMTPS id D78C1385782F for ; Thu, 2 Dec 2021 20:48:52 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org D78C1385782F 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 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 X-Spam-Status: No, score=-3.1 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, JMQ_SPF_NEUTRAL, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL, SPF_HELO_PASS, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 02 Dec 2021 20:48:54 -0000 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