From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=5.0 tests=MAILING_LIST_MULTI autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 14592 invoked from network); 10 Mar 2023 16:30:17 -0000 Received: from minnie.tuhs.org (50.116.15.146) by inbox.vuxu.org with ESMTPUTF8; 10 Mar 2023 16:30:17 -0000 Received: from minnie.tuhs.org (localhost [IPv6:::1]) by minnie.tuhs.org (Postfix) with ESMTP id E143241561; Sat, 11 Mar 2023 02:30:11 +1000 (AEST) Received: from mail.ultimate.com (mail.ultimate.com [IPv6:2607:fc50:0:15::100]) by minnie.tuhs.org (Postfix) with ESMTPS id DB5154155E for ; Sat, 11 Mar 2023 02:30:06 +1000 (AEST) Received: from ultimate.com (localhost [127.0.0.1]) by mail.ultimate.com (8.16.1/8.16.1) with ESMTPS id 32AGU2ed008071 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO); Fri, 10 Mar 2023 11:30:02 -0500 (EST) (envelope-from phil@ultimate.com) Received: (from phil@localhost) by ultimate.com (8.16.1/8.16.1/Submit) id 32AGU2OD008070; Fri, 10 Mar 2023 11:30:02 -0500 (EST) (envelope-from phil) From: Phil Budne Message-Id: <202303101630.32AGU2OD008070@ultimate.com> Date: Fri, 10 Mar 2023 11:30:02 -0500 To: tuhs@tuhs.org References: <20230310115145.7F23118C080@mercury.lcs.mit.edu> In-Reply-To: User-Agent: Heirloom mailx 12.4 7/29/08 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID-Hash: LJJVFALGWMD2P3RKBIF3PXMQVJ24Y5YL X-Message-ID-Hash: LJJVFALGWMD2P3RKBIF3PXMQVJ24Y5YL X-MailFrom: phil@ultimate.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header X-Mailman-Version: 3.3.6b1 Precedence: list Subject: [TUHS] Re: I can't drive 55: "GOTO considered harmful" 55th anniversary List-Id: The Unix Heritage Society mailing list Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: ron@ronnatalie.com wrote: > Multilevel breaks are as bad as goto with regard to structure violation. Back when I was in compilers (so long ago, that it was the DEC PDP-10 FORTRAN compiler(*)) my recall is that break/continue never generated irreducible flow graphs, as goto can: https://en.wikipedia.org/wiki/Control-flow_graph#Reducibility I still remember the days when you could find C code written by PASCAL programmers, littered with condition variables on loops, and if statements to not execute the tail of the loop body if the loop condition was false. (*) The FORTRAN compiler was written in BLISS-10, which had labeled statements, and a "leave