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=-0.8 required=5.0 tests=DKIM_ADSP_CUSTOM_MED, DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FROM,MAILING_LIST_MULTI, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 8588 invoked from network); 12 Jun 2023 22:10:09 -0000 Received: from minnie.tuhs.org (50.116.15.146) by inbox.vuxu.org with ESMTPUTF8; 12 Jun 2023 22:10:09 -0000 Received: from minnie.tuhs.org (localhost [IPv6:::1]) by minnie.tuhs.org (Postfix) with ESMTP id 81A094144E; Tue, 13 Jun 2023 08:10:02 +1000 (AEST) Received: from mail-oi1-x236.google.com (mail-oi1-x236.google.com [IPv6:2607:f8b0:4864:20::236]) by minnie.tuhs.org (Postfix) with ESMTPS id 68633410DC for ; Tue, 13 Jun 2023 08:09:54 +1000 (AEST) Received: by mail-oi1-x236.google.com with SMTP id 5614622812f47-39c84863e7cso2599014b6e.1 for ; Mon, 12 Jun 2023 15:09:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1686607793; x=1689199793; h=content-transfer-encoding:cc:to:subject:message-id:date:from :references:in-reply-to:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=TJm4Ak9MzBQ9KufdMd8/TqaDrTF0Yp7/p26vzEJAsC8=; b=I3B8Rz0FV2L0hoJuaV6VuS9TNOq9ae+AQuzOUxK3ca16XIMmEDrTshYC+QcH5jRaTb HWa1U0gegYJoRRzryOkWLBfHvrxYWXGYzpo5NVrd/LFC3SgvuAxaYfDdUqv3EUNHCTJZ Sq1OV9YOCfQfJvcpO60LMiZ1lHsvQ0RackdwFmbD11GJz3hAvgNgHdumVD/Lc5btMi28 CekzSu0XxYOVqbRpHmX23KG+TG782Fz/jUVjr2joXkEwtC9nqrP3md8e2cGH4axLqGc0 fQegsv95iYVHBI1WwXsZCalNgrKir9ieTkTfr6UWifb7o6JVyp65XuAwMNTaHhXMb63e NMyw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1686607793; x=1689199793; h=content-transfer-encoding:cc:to:subject:message-id:date:from :references:in-reply-to:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=TJm4Ak9MzBQ9KufdMd8/TqaDrTF0Yp7/p26vzEJAsC8=; b=CL7XDvv9y0prZ9RQSRxAFnHoxvP92p7nAsD2PejJZISdXqjXl7V6oZPcQeShkWl5qk hj83Bi7Ka4wYRMBWPrgYF4J8gi00aikDxxJHR/Vqj0f7FVJpY/U5EXJdZUR8Kbz4ubt8 x9lKk4cLqb97fvhPML0ujbQ6A4DnOgSihzYwVVfLsV+zDinRq/VuJKQE2tXqhxiVua/n Oeb4eOM4/DH8I+HU3d6mflq32+Yyl2Lu0EggXPfmbgEe9V2N27+gOI00Nps7V5AxVut6 nQVlC4QTFUTf8I9JY6V4Dw9JNjnNnGSx75Bkb9gcus89CLDZhsNQXcnRxZIOmGi4H6W/ 6T/g== X-Gm-Message-State: AC+VfDwkBunEKN3RNd0XcgES9Wl+YY3EaXTauJUweKmzkV8HO4Pki36G hPZEwFB6av5gc7xp0BPL83uQ/lzQzvlKPAuKy4Bh3zr0 X-Google-Smtp-Source: ACHHUZ50rst02nsPGwllNyrw1vKh48yszax9mGy5AfQe6t1Gl3JM6Swt6BiCc8kWIfFeBIouuX7PMxCtQWIvnZDPmRs= X-Received: by 2002:a05:6808:3014:b0:39a:ac4c:8f3e with SMTP id ay20-20020a056808301400b0039aac4c8f3emr5909057oib.2.1686607793331; Mon, 12 Jun 2023 15:09:53 -0700 (PDT) MIME-Version: 1.0 Received: by 2002:a05:6a10:f48f:b0:4c1:7ec0:eb04 with HTTP; Mon, 12 Jun 2023 15:09:52 -0700 (PDT) In-Reply-To: References: From: Paul Winalski Date: Mon, 12 Jun 2023 18:09:52 -0400 Message-ID: To: Clem Cole Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Message-ID-Hash: 7BRCT4CC5WK2YLNBEIARKTNHTV65LWDR X-Message-ID-Hash: 7BRCT4CC5WK2YLNBEIARKTNHTV65LWDR X-MailFrom: paul.winalski@gmail.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 CC: The Eunuchs Hysterical Society X-Mailman-Version: 3.3.6b1 Precedence: list Subject: [TUHS] Re: crt0 -- what's in that name? List-Id: The Unix Heritage Society mailing list Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: On 6/12/23, Clem Cole wrote: > > WRT to BSS -- Block Start Symbol (and sometimes Block End Symbol in some > later assemblers) I believe was (were) part of the original 704 assembler= s > from United Aircraft reserving a labeled block of uninitialized space in = a > "DUMMY SECTION" (or DSECT) for a hunk of storage. The OS is going to loa= d > everything together. So, a big feature of the United Aircraft assembler w= as > to help control memory layout and collect like (common) hunks of things > together (i.e., code vs data). The whole idea of BSS was to get the load= er > to reserve space that did not have to initialized. As I understand it, t= he > standard IBM FORTRAN (FAP) and Assembler (MAP) for the 709 and 7090/94 > picked it up, with the new FORTRAN compiler being the big driver. > =E1=90=A7 I don't recall either BSS or BES pseudo-ops in the System/360 assemblers for DOS/360 and OS/360. I think that by then they had been replaced by a more generalized concept of PSECTs and DSECTs. I forget now the details of how Fortran uninitialized common blocks were implemented in S/360 object language. It was the job of the link editor to overlay all such symbols with the same name, and if there was no explicit initializer, to allocate space for them in uniniitalized memory. One thing to note is that, at least in DOS/360, such memory was not zeroed out. It contained random garbage Security wasn't a concern in closed, raised-floor computer shops and you didn't want the program loader to waste time zeroing out memory anyway. -Paul W.